I Did It On Purpose

This sounds a bit like a confession and in a way it is. I’ve done something that shouldn’t be done and did it knowingly. Fair confession!

Now and again I try to find something out for myself by running an experiment. A scientist would advise that they aren’t experiments at all but amateur fiddling, and I accept that. To qualify as scientific there needs to be a control set up for comparison purposes and various readings taken. All I do is observe for the most part.

I keep a soft coral reef lit by a bank of fluorescent tubes, equally mixed marine white and marine blue.

The last experiment – sorry, fiddling – I did before the current one concerned cover glasses. I don’t habitually use cover glasses nowadays though I used to. They were used as they reduced the amount of evaporation significantly. I noticed in the morning when the lights came on that the cover glasses were heavily condensed underneath, so much so that there were droplets visible all over them. I wondered if this condition would affect the light input into the aquarium and therefore the corals. It took a fair while each morning for the lighting heat (fluorescents) to clear the condensation.

So I took the cover glasses off and noted the date. The cover glasses were left off for a full six months and I watched the corals with care, wondering if growth rates or colour would change.

During the six month period the aquarium was treated as normal, there wasn’t any change in the feeding regime or maintenance schedule. I had to increase the top-up amounts as evaporation increased, but this was expected.

I have to admit to some disappointment as I had assumed that the corals would respond to the increase in light. The light input to the seawater would be affected to some extent by the presence of glass covers even though they were kept clean, and the period each morning when heavy condensation was on the glasses also no longer had any impact on the light. However, the corals showed no change whatsoever, either in growth rates or colour. The growth rates and colour had always been good with the cover glasses on, but, as said, removing them had no effect (accept for the evaporation rate).

The cover glasses have never been replaced as I assume the gas exchange should be better at the seawater surface. Hmm, I wonder. Maybe I could check that someday, though there isn’t any real necessity as the fish are clearly healthy with a normal gill beat.

My latest fiddling has been to do with feeding. I always feed carefully as this is where the phosphate comes from, and a lot of the nitrate is generated. Both are undesirables not least because they are fertilizer for nuisance algae. I haven’t any nuisance algae and never have had.

I have a very low fish load consisting of one Flame Angel (Centropyge loriculus) and one blue damsel (Chrysiptera cyanea). This represents a very low bio-load on an aquarium that has been running for 6½ years (i.e. the aquarium is aged and fully mature). I was interested to see if the bio-filtration, all those hardworking bacteria, could cope with a sudden increase in load.

I used to use canister filters for bio-filtration but fairly recently have removed the media as the rocks are live (when the aquarium started they were dead and inert). The period between that action and now means that any bio-filtration has transferred to the rocks. After the canister filter media was removed there wasn’t a problem of any sort and nitrate didn’t appear (there isn’t a nitrate reducing device on the aquarium nor any Caulerpa algae etc). This shows that the bacteria on and within the rocks cope.

I didn’t want to upset the balance of the aquarium by introducing any new fish, I’m very happy with the set-up which has been very successful. How could I increase the bio-load?

I decided to overfeed. Yes, that’s right, doing that which we say over and over shouldn’t be done! As said previously, I feed very carefully and am fully aware of the fish’s appetites and what is enough. They are fed a basic of marine flake and varying frozen foods, mainly enriched brine and mysis shrimp.

I carried out my normal Sunday maintenance and that evening, when a normal feed was due, I fed the usual amount. At the point when I normally cease to feed, I continued even though the fish weren’t interested. About ½ of the normal amount was fed additionally. This overfeeding continued for a full week and ceased on the following Sunday evening when a feed was due, this feed reverted to normal.

During the overfeeding period I watched the aquarium more carefully than usual, particularly the fish in case there was any sign of discomfort. An indication like this could have signaled the appearance of ammonia and nitrite. There weren’t any negative indications whatsoever.

Mid-week I did an ammonia and nitrite test just to be sure, there wasn’t anything detected. At the end of the week I did a nitrate and phosphate test, again nothing was detected. (It should be pointed out that I continuously run an anti-phosphate filter.)

It is now about 3 weeks since the testing began and nothing has appeared that shouldn’t be there.

Only one indication of the additional feeding appeared, and this was heavier than normal algae on the aquarium viewing glasses. This was not heavy, but there was more. This was easily cleaned off during maintenance.

So I have to assume that the bio-filtration is quite capable of holding its own, though the percentage increase in the bio-load because of the food is…I haven’t a clue! The amount of food put into the aquarium (flake and frozen) was 50% higher than usual. The Baensch Marine Atlas advises that, assuming a protein content of 50%, one gram (about a teaspoonful) of flake can add 336 parts per million nitrates, this is after the nitrogen cycle process completes of course.

It could be commented that there wasn’t an effect as the fish load is so low. Is this correct though? The size of the bacteria populations will be dependent on the demand made upon them.

I was surprised that there wasn’t any effect apart from some glass algae though. I thought bio filtration couldn’t adapt that quickly.

Then I had a further thought. My aquarium, particularly at night, displays a large population of tiny life forms. Any food available that has not been touched by the fish could well have been eaten by them. Nevertheless, the food has gone into the aquarium and the process of consumption would lead to waste. So again the bio-filtration must have coped. It also demonstrated that live rock can complete the full nitrogen cycle, from ammonia to nitrogen gas, thus the lack of nitrate.

As already said, this wouldn’t qualify as a definitive scientific experiment. I found it interesting though, and at the least it gave me confidence in the live rock ability now that the canister filter media is no longer there.

Now, may I point out that my aquarium is very mature and also that I can claim experience. Overfeeding is a definite no-no and should be avoided. Seawater quality is the number one priority and overfeeding will not help at all! I only did it for a week and reverted to careful feeding afterwards.

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Is Frozen Fish Food Beneficial To Fish Or Just Handy To Aquarists?

Unless the aquarium is a reef with corals only, then there are going to be fish present. Whatever species these fish are there will not be sufficient food in the aquarium to meet their needs.

One of the most pleasurable parts of keeping a marine aquarium is feeding the fish. Maybe this is because there is direct interaction between the fish and the aquarist. There are a few fish that have real characters and become pets individually, but most fish only respond to movement outside the aquarium as, after time has passed since their introduction, it triggers their food response. They come to the front of the aquarium – ‘Where is it then?’

Marine fish need more than just ‘some food’. They have evolved to eat a particular type of food on the wild reef, or they are omnivores. Having said that, most fish will respond to any food once they recognize it as food. This recognition may initially come from their tank mates’ reaction.

Marine fish need to eat generally what Mother Nature intended. This could be algae which is a good example as some fish, for example surgeons, need it to remain healthy. So the aquarist cannot simply decide that a particular food is good and sufficient simply because the fish eat it.

One of the best base or foundation foods is flake. Flake is formulated by nutritionists to generally supply all the protein etc that marine fish need. This doesn’t mean to say that this is all the fish get; the diet needs to be varied.

Most aquarists use frozen foods as a variation as it comes in all sorts of guises, either mixtures or particular types. Two types that are very popular are brine shrimp, preferably ‘enriched’, and mysis. I use them myself in addition to other types including flake.

Flake as said is produced to generally meet the needs of marine fish and can be said to be nutritious. What of frozen foods though?

Using frozen food is straightforward as it usually comes in blister packs that the aquarist can store in the freezer. Getting it ready to feed the fish is also easy, all that needs to be done is to release one blister, if necessary reduce the amount by cutting it when still frozen, and then place it in an egg cup or similar. After a little RO (reverse osmosis) water or seawater from the aquarium has been added the food thaws quickly. Frozen food should not be thawed in a microwave as it has been anecdotally reported that this reduces the nutrition value.

So the question about the food being handy for aquarists has been answered – it certainly is. But is it nutritionally good for the fish?

I am not qualified to talk about nutrition. However, I can sensibly speculate and turn to human frozen food to do so. I used to wonder if frozen food for our consumption would be as good as the fresh variety. I used to assume that it wasn’t, as surely fresh food must be best! However, nutritionists state that the answer depends on the age of the food when it was frozen, if it was lying around or in transit for a good period the nutritional value would decrease. If the food was frozen immediately or nearly immediately then the nutritional value would be equal to fresh or even better if the fresh type had been harvested a while ago.

So perhaps this could be applied to frozen fish food. When were, for example the brine shrimps, frozen? I would imagine that there will not have been much delay in applying the freezing process as shrimps of that size are not suitable for keeping out of water and when in water they would have been living. The same would apply for other types of ‘live’ frozen food. If the food was frozen immediately the nutritional value shouldn’t have deteriorated. The question of what food value existed pre-freezing, that is when in its live state, is another matter. Brine shrimp and similar are not said to be particularly nutritious though there is obviously nutrition present. They are also said to give valuable roughage. Sometimes they are sold as ‘enriched’ which means the shrimp were fed a rich diet, which should be reflected in the frozen state if the freezing process was not delayed.

There are other frozen foods besides shrimp varieties and I would guess that the same applies, when were they frozen?

I feel fairly certain that a nutritionist knowledgeable in this area would have a lot more to say. However, the consideration of ‘when was it frozen’ would seem to cover the basics at least.

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Brine Shrimp – Any Use In The Marine Aquarium?

Several different foods suitable for marine livestock could be used for overall feeding and this variation is a good thing, as it increases the chances of fish etc ingesting all that they need. Whatever food is used, it should be marked as ‘marine’ – flake food for example. The aquarist should ensure that particular livestock receive sufficient natural foods, such as algae, if this is important to their well-being.

Most aquarists feed frozen and flake foods. The flake is rich and good to use provided overfeeding doesn’t occur. The same point about overfeeding applies to frozen foods as well, but not the richness. Frozen foods are very useful and it is good to include them. Mysis shrimp is an example.

Another frozen food that could be used, in addition to any other flake and frozen type to increase the food base that is being offered, is brine shrimp. It would be unusual to find a frozen food supplier who did not stock this. The shrimp are in flat packs made up of ten or more blisters, and each blister is designed to be removed individually. Once removed, if necessary it can be further reduced in size as the blister portions are easy to cut when frozen. Then the food can be placed in a small container such as an egg cup and some RO (reverse osmosis) or seawater added, after which it should be left to defrost. Defrosting should not be speeded up by using a microwave or hot water as it has been reported that the nourishment value of the food is reduced.

Once defrosted the water that the food is in should be drained off as far as possible before the food is put into the aquarium, where it will be caught by the seawater currents and float off. It shouldn’t last long – fish find it attractive.

I am not a food specialist in any way. What I understand from reading is that frozen brine shrimp is not particularly nutritious, less so than mysis shrimp for example. In its basic form from frozen it has good roughage value. The food can be nutritionally enhanced when it is alive by what is fed to it, and brine shrimp that has been reared in this way is often described as ‘enriched’. One of the foods that could have been fed to achieve this is spirulina algae. This could be stated on the package.

Brine shrimp does not have to be used from a frozen state, it can be fed live. Many local fish shops (LFS’s) supply them live and pre-packaged, though in my area the availability has diminished a great deal. When purchasing them in this way, have a look at the package – usually a clear plastic bag – and ensure they are alive. There’s not much point in paying for live when they’re not.

Another way of obtaining live brine shrimp is for the aquarist to produce them. This is not difficult. What are required are agitated salt water (some from a seawater change perhaps), a suitable container (containers designed for the purpose of breeding brine shrimp are available) and brine shrimp eggs. The eggs go into the container and after a while very small shrimps appear. These can be recovered by a fine net or even a pipette type device. All instructions are with the container. Some containers are a complete kit.

If the aquarist requires bigger brine shrimps they will have to be fed and grown on – once the egg-sac has been consumed feeding is required.

I used to produce brine shrimps and quickly learned that when the instructions advise ‘a small pinch of eggs’ that is definitely what is required. At first I put in too many eggs and ended up with far too many shrimps. I also used to put them in the aquarium when small, just as the egg-sacs had been more or less used up. The fish I kept, which were small, used to eat them as fast as they could, and even some of the corals, such as toadstools, used to tuck in.

I had the ‘brilliant’ idea of dispensing with the breeding container and put the eggs directly into the aquarium – it contained warm moving salt water after all. Unfortunately this was not successful, and I put the failure down to insufficient turbulence to move the eggs.

I now use ‘enriched’ frozen brine shrimp among the other foods that I feed, which includes other frozen varieties and flake.

Brine shrimp is fine for the marine aquarium, but needs to be mixed with other foods and not be the only food. When I say mixed with other foods, I do not mean literally. Brine shrimp could be fed for one meal on its own; the next meal could be flake, the next mysis shrimp, the next flake, and the next brine shrimp again. There isn’t any reason why the number of varieties could not be greater. Advanced aquarists sometimes mix different frozen and flake foods, divide them into portions, and freeze them. Others try fresh foods mixed and freeze them.

Brine shrimps are very good for enticing reluctant feeders to eat- maybe a new fish has been added. They swirl around in the currents and the majority of fish chase them, and hopefully the new fish will join in once its initial shyness has gone. They are also captured by some polyps and ingested.

Brine shrimps are a good addition to the food arsenal kept by the aquarist. Frozen is the usual type used and this is understandable = just pop them in a box with the other frozen fish foods and store them in the freezer.

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Food For Thought

Food is required by all life for energy and general health. Lots of food of the wrong type may provide some energy but the contents will not supply the general needs of the life form. So it is important to feed the life in the marine aquarium the correct type of foods and at the same time not overfeed.

On the wild reef different life forms have different niches for food. There are predators, some general, some very specialized. There is life that eats a particular item, such as herbivores eating algae. There are also omnivores that will eat almost anything they come across, thus taking advantage of a wide range of food sources. The needs of these different types stay with them in the aquarium.

Again on the wild reef with its abundance of different life forms hardly anything goes to waste, there is something in the food chain that will clear it up. In addition, the huge volume of seawater over the wild reefs can ‘absorb’ any small amounts of food created pollution. This is not the case in the aquarium. Though modern systems attempt to replicate the wild reef as near as possible there isn’t a way that all the life variations can be represented. The very limited gallonage in an aquarium, even one considered to be very large, is subject to food pollution.

The aquarist can deal with algae by having herbivorous fish, crabs and snails present. Detritus can be dealt with to an extent in the same way. In a fish only system with live rock (FOWLR) and particularly in a reef system there should be a considerable number of minute creatures living among the rocks which no doubt will make use of excess food. Where does this excess food come from? In a FOWLR the aquarist is more than likely to stock the aquarium to its fish capacity. This is also usual in a reef system, though the fish stock is, or should be, lower. All of these fish, and any other creatures, need to receive supplemental feeding. The food that might be available in the aquarium is insufficient.

This supplemental food provided by the aquarist is usually either frozen or in flake form. There are variations but it is these two that are the main foods used. It is here that the potential danger lies. Novice aquarists more often than not do it – overfeed. Experienced aquarists, though more careful, ‘overfeed’ as it is usually impossible to ensure that all food is eaten and some inevitably end up in the rockwork. It is to be hoped that the tiny creatures in the rockwork will make use of it.

We should not be too hard on the novice aquarist who overfeeds. There are two reasons for this bad practice, the first is that the aquarist is concerned that enough food is available for the livestock, and the second is that feeding is a very pleasurable experience. So the error is made for the correct reasons.

A comment has been made about the restricted seawater capacity of an aquarium. One gram of flake food (say a teaspoon full) with a protein content of about 50% can convert to 336ppm (parts per million) nitrate*. In a reef aquarium the guideline for this type of aquarium is 10ppm or lower, and in a FOWLR as low as possible, preferably about the same. Though varying seawater gallonages should have some effect it is clear that pollution is a threat.

So what’s to be done? How can the pollution threat be reduced?

The aquarist should be providing a reasonably wide spectrum of supplementary food. As said, this is usually frozen and flake. It is obvious that to prevent pollution the amount of food of either type needs to be restricted, but how? How can the aquarist be happy that the livestock have eaten enough?

It is said quite often that fish and other marine life should be fed little and often, feeding only enough as can be completely consumed in two or three minutes. This is quite correct, first because reef life usually feeds continuously in the wild and second because the life will be hungry and more likely to chase down all the food.

Unfortunately, modern lifestyles do not allow ‘little and often’ feeding in many cases, as jobs call the aquarist away.

The first consideration is an auto-feeder. These feeders can be programmed to release a small amount of food into the aquarium at set intervals. Some are quite good, others not. The top of the aquarium must be open, and there needs to be an adequate area where the feeder can be securely fixed. Some aquarists see these auto feeders in the same way as, for example, automatic water top-up devices, in other words automate the aquarium system in all ways possible. All automation is good, correct? This is, in my opinion, wrong, some automation is good. Auto feeders though should be viewed as a potential way to feed little and often, nothing more.

These devices distribute flake food. For flake to be released it has to be completely dry, and the device is over the top of the aquarium in a damp area. This means that some of these devices fail from the start as the food becomes damp. At least there should be some kind of food drying mechanism – some feeders have a small fan that moves air through the food chambers.

Another problem with feeders is that they drop flake into the aquarium, and dry flake will float. If there are any weirs, overflows etc the food may go over these before being consumed.

Personally I don’t use them, preferring to feed direct twice daily. This means that the livestock will receive more food but with longer intervals between feedings. This doesn’t matter provided feeding is done carefully, and of course it fits in with the lifestyles of most aquarists.

The amount of food that will be consumed by the livestock will vary aquarium to aquarium as obviously the amount of livestock will vary. The aquarist needs to discover the quantity of each type of food, frozen and flake, which is required. This is easy to do.

Take frozen first. Frozen foods, such as brine or mysis shrimp, are usually supplied in blister packs made up of many blocks. The aquarist needs a very small container – an egg cup is ideal. Take one frozen food square from the pack and chop into four parts. One of these portions should be placed in the egg cup, and some aquarium seawater or RO (reverse osmosis) water added, enough to cover the food. Allow the portion to de-frost completely, so that the shrimps float free. Do not accelerate the process by using a heat source or a microwave, as it has been reported that this reduces the nutritional value of the food.

When fully de-frosted, pour off the liquid as far as possible. Then allow one half of the food to enter the aquarium. The food will be caught by the seawater currents and will move around the aquarium which should attract the fish. Once the food has gone the fish will probably continue swimming around eagerly looking for more. If so, repeat the process de-frosting more food if necessary, and continue to do so until the fish indicate they have had nearly enough. This is shown when the eagerness displayed has reduced.

The aquarist now has an indication of the amount that will be required for each feed. However, this doesn’t mean that the one or two or whatever blocks of food can be de-frosted and put in the aquarium all at once, this would present too much food to the fish and some would inevitably be missed. The aquarist can de-frost the full amount, but the food should still go into the aquarium in portions. This helps to ensure that it will all be eaten. Also, each feeding should be seen as an individual exercise, as sometimes fish can be less interested in food than at other times. It is better to underfeed than overfeed – if a little underfed the fish will probably be a little hungrier the next time. Any de-frosted food left over should not be re-frozen but discarded.

Flake food is dispensed in a similar manner. The flake should always be that which is described as suitable for marine life. The egg cup or similar is again required. Also, it is helpful to have some tweezers available, plastic if possible. Most fish, once they have seen other fish eat flake and have recognized it as food, will be attracted to it.

Take a good pinch of flake and place it in the egg cup. Try and ensure that the food is in flakes and avoid any very small bits as the fish will usually go for the larger flakes and the bits could be caught in the rock work. Put some seawater or RO water in the eggcup so that the flake goes soggy. Now take a very small pinch of flake with the tweezers – it will look awful and will cling to the tweezers. Release the wet flake into the aquarium where it will open up. The fish should chase it down and quickly consume it. They will no doubt swim around eager for more, so do the same thing again. As soon as this eagerness diminishes, stop feeding. Again, the aquarist has an indication of how much food is required. It may be that when using flake the fish lose their eagerness more quickly – this could be because the flakes can be quite large and the food is very nutritious. The aquarist should remember that flakes are very nutritious and less will usually be enough. Again, each feeding should be treated individually and a reduction in eagerness watched for. Any excess flakes should of course be thrown away.

With some fish, such as surgeons, there is a requirement for algae to keep them in good health. Though flake containing algae could be used, if there isn’t much algae of the correct type available in the aquarium the aquarist could put some in, in fact, this is a good practice. This algae is of the dried variety which is supplied in sheets, such as Nori. Health food stores often have this as well as pet retailers.

The algae sheet can be reduced in size according to the number of surgeon fish present, and then held in place against one of the viewing glasses with an algae magnet. It will move with the seawater currents and the fish will spend much time grazing on it, much to their benefit. It is a good idea to ensure there is algae present for such fish every other day – some aquarists keep it present every day. The aquarist needs to remove anything that is unused and likely to float off round the aquarium. It also needs to be remembered that feeding algae will reduce the appetite at feeding times of the fish that have eaten the algae.

Some fish, despite others eating well and giving a good example, do not overcome their shyness and natural instincts and remain in a part of the aquarium where food doesn’t reach. In this case, once the other fish have eaten, they need to be individually fed.

Feeding will produce some level of nitrate and phosphate even if done carefully. This increase in pollutants is dealt with by routine seawater changes. The changes offer advantages in addition to the dilution of pollutants and should be done in all aquariums. Some bio-filtration methods will generally deal with nitrate, such as live rock. Nevertheless, routine seawater changes should be completed.

Feeding carefully reduces pollution increases that can only be good for the live stock, which in turn are properly and sufficiently fed. Also, that most important aspect of feeding is still present – the aquarist’s enjoyment.

(*Reference: Baensch ‘Marine Atlas.’ Helmut Debelius & Hans A. Baensch)

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Brine Shrimp – Should You Use Them In A Salt Water Aquarium

Feeding the livestock in a marine system is of very great importance. All living things need food to obtain energy and remain healthy. Without an adequate food supply – adequate in both quantity and quality – livestock will soon start to have problems.

Brine shrimp have been in use for many years. They can be obtained frozen and live and, though I haven’t seen any for a while, they are also available dry.

One of the tricks that can be employed when a new fish is reluctant to eat is to use brine shrimp. When they go into the aquarium the other resident fish chase them with gusto and often the new fish will become involved in this and take a few. If the new fish is on its own a brine shrimp or two dancing in the current is hard to ignore.

I would guess that the majority of aquarists use the frozen type. These come in a flat pack which is divided into segments, each segment is broken free as required. The segments can be cut down into smaller amounts according to need. Before the food is introduced it needs to be defrosted and this process should be done in seawater or a little reverse osmosis water. The food should be allowed to defrost on its own without the assistance of a microwave or similar. Some aquarists rinse the defrosted food before use.

The best frozen shrimps to use are those that are ‘enriched’. Brine shrimp is not particularly rich though it probably provides good roughage. Some aquarists insist on a product that has been irradiated, which means that there will not be any disease causing dangers present.

Live brine shrimp are usually purchased from a local store by the bag. The shrimp are definitely fresh and the storekeeper should be able to state their origin and if they have been enriched. Some aquarists are concerned about the possibility of disease. I used live shrimp for two years or so from a local store and never had a problem. I ceased using them as the supply to the storekeeper dried up. At that point I switched to frozen.

Brine shrimp are available dried. I did try them once and found them not to be particularly worthwhile for the simple reason that they had to be pre-soaked for quite a time or they would float around on the surface – once soaked they did sink but the fish were not overly enthusiastic. As said I haven’t seen the dried variety available for a good while. I also wondered about the nutritional value. Without any evidence I always had the feeling that this was poor.

Producing live brine shrimp at home is easy. All it needs is a suitable container with vigorous water movement, a convenient location and a supply of eggs. The eggs have become much more expensive (or they have in my area) and it may be found that the frozen variety is more economical. There are brine shrimp hatching kits available commercially, and these come with full instructions which are straight forward. Just don’t put too many eggs in like I once did: there’ll be so many brine shrimp they’ll need feeding themselves before they can be used. Using tiny newly hatched shrimp is good for corals and fish.

Brine shrimp are not a complete food in themselves, more of a supplement. There isn’t a reason why an aquarist couldn’t use them every day, but it would be better to use them along with other ‘supplements’, a good example is mysis shrimp. A fully nutritional food such as marine flake and the like should be the base diet. In addition attention must be given to the dietary requirements of livestock. Surgeon fish for example will usually eat brine shrimp without problem, but they need more nutrition as mentioned plus a good supply of suitable algae.

Brine shrimp is an excellent part of the marine aquarist’s food store. Stored and used properly it will add dietary variety and the fish seem to enjoy chasing it down.

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Should You Run Your Protein Skimmer Full Time Or Part Time?

The protein skimmer assists in the removal of dissolved organic compounds (DOC’s) from the water column. The protein skimmers manufactured nowadays are normally exceptionally efficient – as long as they are kept clean!

So what do I mean by running your protein skimmer full time or part time?

Well basically a protein skimmer which is run full time is turned on 24 hours a day 7 days a week whereas a part time skimmer is on for less hours in the day – 12 for example.

So why would anyone consider this?

You have to look carefully at what you are keeping in your saltwater aquarium. If you are keeping fish only then I would recommend without hesitation that the protein skimmer be run fill time. Fish produce a lot of waste and we have to feed them so the protein skimmer assists in the removal of these items as well as others from the water.

If you keep a coral only or a mixed reef tank then perhaps it could be different. I say the word perhaps as you need to look very closely at what you keep in your aquarium. The reason for this is that we are interested in the load on the aquarium i.e. how much waste is being produced which the protein skimmer can then process. In a coral only aquarium then very little bioload should exist as corals put very little strain on the system. This does not mean that you do not need a protein skimmer as I personally would never have a saltwater aquarium without a protein skimmer installed.

In a mixed reef aquarium then you obviously have corals and fish, therefore like the fish only aquarium the fish are being fed, due to the feeding waste is produced which could easily impact water quality. Yet, how many fish are in the aquarium? How large are the fish?

What you can do is review your protein skimmer over a couple of weeks. Ensure that you have optimum water quality and then check your collection cup at the end of the period and see how much waste has been produced. If the cup is over half full then realistically you probably need to keep the protein skimmer running full time to ensure that everything is removed. If the cup is less than half full then faesibly you could potentially use a part time skimmer.

Of course this is not set in stone as each aquarium system is different. The decision ultimately comes down to you based upon your particular setup.

So why do it?

There is a lot of debate as to how much good is removed by a protein skimmer as well as bad. As protein skimmers have evolved over the years they have become more and more efficient. Due to this efficiency they can remove a huge amount from the water. This is great in one way as it assists us in both creating and maintaining the water quality which our aquarium inhabitants require however what else is removed?

Personally I have absolutely no idea. I am not a scientist and do not have the tools, skills or knowledge to be able to analyse the output from a protein skimmer and see what it contained. All I know is that it is brown and exceptionally stinky!

It is believed that some of the items potentially removed by the protein skimmer is used by corals as food. Corals receive the majority of their energy from the lighting which is provided to them, however they do receive a good amount from food captured in the water. This could be the likes of phytoplankton, zooplankton etc. Have you ever watched a documentary on the television about natural coral reefs? Have you seen how many particles are floating about in the water? Loads aren’t there – in the aquarium we do not have this amount as we have to use man-made devices in order to keep the water clean.

So potentially if you run the skimmer part time some of this life will not be removed and can be used by the corals as food.

There have been reports that when this is performed it has been noticed that the corals appear to have better colour and better polyp extension.

Another method is by actually feeding the corals yourself. You can purchase various ready made containers full of coral food which you feed to the aquarium. There are also various methods you can follow to make your own coral food. I will cover coral feeding in a future article.

Would I do it? – maybe but only if I was absolutely positive that it was not detrimental to water quality and I would be testing the water all the time.

Would I recommend the beginner do it? – Probably not – not just because they are new to the hobby but the aquarium is also new and needs to age a bit. Perhaps if only corals were being kept but even then I think that it should be run full time until the aquarists gains experience.

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