What Is Natural Aquarium Filtration

There is one thing that I have learnt in all my years of keeping aquariums - do not underestimate nature!

It still amazes me today how powerful natural aquarium filtration actually is and how many ways there are to actually filter an aquarium or provide additional nutrient export by using the power of mother nature.

Nowadays whenever I am asked for my recommendation as to the best way to filter a marine aquarium I always mention natural filtration. In my opinion and this is purely my opinion live rock mixed with a remote deep sand bed has to be the ultimate natural based filtration available at this moment in time.

The prime advantage of using natural based filtration methods is its efficiency and the advantages that it gives to the aquarist.

A lot of people however have never heard of natural filtration never mind actually understand what it is.

So what is natural filtration?

Any filtration technique applied to an aquarium actually does have an element of nature in it - the bacteria however in a lot of occasions the container upon/in which the bacteria lives is not natural - it is manmade.

A good example of the above would be a canister filter. The bacteria is natural, however the holding device if you will has been manufactured.

Therefore a good way to explain natural filtration is that it is where the bacteria live in any area which has not been manufactured by man.

This is not a set rule however as there are exceptions to natural filtration. One of which would be using macro algae as a nutrient export tool.

Numerous natural filtration methods can be employed in the home aquarium. Some can be implemented for use as a primary filtration method whilst others can be utilised as an additional nutrient export tool.

As already stated natural filtration can be and is an exceptionally powerful tool. Think about the ocean - it is huge, however the natural filtration devices which are in use in the ocean are very similar to what we can use.

The rock structures on the coral reefs are similar to live rock filtration, grass beds are similar to a refugium/macro algae, mangrove swamps are a much larger scale of mangrove usage in the aquarium etc.

Can you see how powerful this type of filtration can be. The ocean has been filtered this way for millions of years and it can and does work in the aquarium.
Although our aquarium are minute compared to the size of the worlds oceans the end result is the same - excellent water parameters.

There is a point which needs to be made however, the filtration has been termed as natural filtration simply because it is similar to what is used in nature or is the same as is used in nature but on a much smaller scale but there will always be an element of human involvement.

That’s right - the care and maintenance. As with all things in this hobby the correct care and maintenance techniques need to be applied and this is no different with natural aquarium filtration. Nature can again be involved in this area for example using hermit crabs, snails etc to keep the rocks/sand clean however there will always be a time where we need to get involved to keep it just right and running at optimum efficiency.

If you are just starting out in this hobby or already have an aquarium and are using man-made filtration then I really recommend that you at least consider natural based aquarium filtration. It is absolutely amazing how powerful it actually is.

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Tags: Aquarium Filter, Aquarium Filtration, deep-sand-bed, live-rock, mangrove, refugium

The Canister Filter - A Thing Of The Past Or Still Useful?

Technology marches on and there are quite a few devices that are available for use with a marine system. The canister filter is not new and has been with us for a considerable period.

Canister filters are made by quite a few manufacturers. They are usually shaped, err, like a canister, though there are models available that are square. As time has passed they have become very reliable.

A canister filter could be considered a closed circuit. Seawater is delivered to the unit down a flexible tube, passes through the canister media and is then returned to the aquarium through another flexible tube powered by a built-in pump. It is best if the intake and outlet are at opposite ends of the aquarium, though perhaps this is not so important nowadays when the high flow rates within the aquarium are considered. Nevertheless, it is best to keep the intake and outlet apart.

What can the canister be used for? Biological filtration is the first use that comes to mind. Though filtration this way has been superseded by live rock an aquarium can still be successful using a canister, and many aquarists still do. The cost of live rock is high, and so canisters find a use. They need to be filled with a good bio-media, and this media needs to be protected by efficient mechanical filtration, such as sponges and filter wool. The cleaner the bio-media is kept, that is, kept clear of sediment, the better. The canister needs to be sized to the size of the aquarium, and the manufacturer’s specifications will include recommendations. One point about these recommendations - the flow rate advised by some manufacturers is often with the canister empty, when it is filled with media it will be less. Consideration can be given to using two smaller canisters so there is a backup. The canisters can be serviced alternately.

Cleaning the mechanical media in the bio-filter is important otherwise the seawater flow will decrease. It is a good idea to clean this media after two weeks. It may be that it remains reasonably clean in which case increase the period to three weeks and so forth. Sometimes it is recommended that the filter should be cleaned when there is a noticeable reduction in the flow rate. This is not really acceptable because for this to happen the media will be very dirty. By cleaning and checking the condition of the mechanical media the aquarist can arrive at a reasonable service period. A watch should always be kept on flow rates even with more regular cleaning because of the importance of bio-filtration - a failure or reduction could result in serious consequences. In addition, the bio-media itself must never be washed in tap water as this will kill the bacteria. If cleaning is essential then seawater should be used, and this can be at a routine change using the old seawater. The media should be very gently stirred with the fingers under the seawater to remove dust and debris. It will never look ‘as new’ but this doesn’t matter.

If the filter is used for bio purposes then the seawater leaving the filter will be low in oxygen. This is because the bacteria that carry out the bio-filtration function are oxygen hungry. The oxygen can easily be replenished by releasing the returning seawater at the surface.

There is an important point with bio-filtration in a canister filter. This is that the ‘Nitrogen Cycle’ will arrive at nitrate and stop. The ‘Nitrogen Cycle’ is the process where bacteria convert ammonia to nitrite, then the nitrite to nitrate. A watch should be kept on nitrate levels, though this should be done in any marine system anyway.

If other means of bio-filtration are in use then the canister is not redundant. It can be used for purely mechanical purposes, that is trapping detritus that is in the seawater. In this case only mechanical filtration such as sponge and filter wool are in use, and these can be washed under the tap. If they are showing any deterioration they should be replaced. This of course also applies to the mechanical filtration within the bio-filter.

The canister can also be used for activated carbon and/or anti-phosphate media. These are put in after the mechanical filtration. Certain anti-phosphate media types with a very fine particle size are usually better in a fluidized reactor, as in a canister they could tend to clog. Cleaning the mechanical filtration area is the same as above, and a note should be made of when the activated carbon and/or anti-phosphate media are due for renewal.

There is another use for the canister. If a small canister set up as a bio-filter is kept running on the display aquarium, or better the sump as connection is easier and the intakes/outlets will not be seen, then a permanently ready bio-filtration unit will be at hand. This is useful for those aquarists who have wisely used a small aquarium for quarantine purposes. This could be required again for quarantine of a new arrival, or as a hospital area for a fish with a problem. There isn’t a need to keep this aquarium full of seawater, but if required it can be filled and the bio-filter is ready.

So the canister filter is not out of date. Modern types are very reliable and much easier to service than the older models, which could be fiddly. Having a canister in the system could certainly be useful.

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Tags: Aquarium Filter, Aquarium Filtration, deep-sand-bed, Equipment, live-rock, plenum

Aquarium Filter Media - Is There Such A Thing As The Best One

The function of the filtration is to ensure that the relevant nutrients in the water are processed. These nutrients occur due to the inhabitants being kept in a closed environment - the aquarium.

Of course life in the ocean also creates waste yet the ocean is so vast that the waste/nutrients are controlled. Look at the oceans filtration - huge sumps, loads of live rock, the biggest deep sand beds ever, mangrove swamps etc.

In our aquariums fish and food are the biggest problems. As soon as you add fish to the aquarium there is a requirement for you to feed it. The trouble is the majority of aquarists unfortunately overfeed. Not on purpose I hasten to add feeding is a pleasurable time and as aquarists we all want to ensure that our fish are well fed.

Fish being fish though will just eat. This is a natural response and is primarily because they do not know when their next meal will come, therefore the gorge.

This causes the problem. There is a lot of food which does not get eaten and starts to decay, other food is passed through the fish’s digestive system either un-digested or partially digested as they ate to much, normal faeces plus urine.

Unless this waste is broken down and processed by the aquariums filtration system then before long the fish will be living in a nutrient loaded soup.

Not nice as I am sure you will agree.

This is why it is so important that a good filtration system is implemented. There are various types of filtration which can be utilised in the aquarium some of which are listed below:

• Canister Filter
• Internal Filter
• Fluidised Filter
• Plenum
• Deep Sand Bed
• Live Rock

In the above examples there are some of these which require filter media. Filter media can be many things - sponge, ceramic rings, plastic balls etc, however it can also be sand or even rock. For example the filter media used in a deep sand bed is the sand itself and the filter media used in live rock is rock.

There are a lot of people who see filter media as being something which is man-made which is added to the aquarium. It is of my opinion that filter media is anything where the required bacteria can function.

Any type of filter media can and will work. The issue is not about where the bacteria live it is how the filtration itself is maintained and how efficient the filtration is.

A good example of this is a sponge filter media. When the filter media is working efficiently the sponge will be clean and not clogged in any way, however over time the sponge if not maintained correctly will become clogged and the efficiency of the filtration will decline.

Another example would be live rock. If the live rock is not kept clean by either manual methods or by the introduction of a natural clean up crew then the filtration may not work at a level of efficiency which is could do if it was clean.

I do admit that there are some filtration media which does allow for more nutrients to be converted. The majority of filtration media finishes at the creation of nitrate. A deep sand bed, live rock or the two combined when maintained correctly will allow for the processing of nitrate as well.

Maybe the article should have been titled ‘Aquarium Filter Media - Which is The Most Efficient’ as it is of my opinion that there is no such thing as the best filter media…just the most efficient.

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Tags: Aquarium Filter, Aquarium Filtration, Aquarium Maintenance, Care, deep-sand-bed, filter media, live-rock, plenum

Addition To My Deep Sand Bed

My soft coral reef has been running in excess of 5½ years. 3½ years ago I decided to add a DSB (deep sand bed).

I know the above periods are correct as I keep a notebook.

The aquarium was running without any problem, the decision to incorporate a DSB was driven by interest. I wanted to see if I could develop a bed that was full of life as described in various articles.

I haven’t the space for a full size DSB, that is one of the size that follows the guideline. It had to go in-tank as well, and fortunately there is a divider in the tank separating the display area from the pump area. The DSB went in the pump area and is very approximately about one twelfth of the base area of the whole aquarium, or perhaps even less. Therefore any effect on the seawater would be minimal (nitrate reduction for example) but, as said, I wanted one out of interest.

It was constructed with fine sand to a depth of just over 4″ (circa 10 cm). I remember that though I had cleaned the sand as best I could, the display looked like it was wreathed in a thick fog for quite a time. After a few hours it cleared without any ill effects.

The DSB sat there looking very clean and tidy for quite a time. Then I obtained a small amount of sand from Peter’s DSB and laid it on the top. This sand was fairly coarse and sits in a very thin layer on top of the fine sand.

The hope for life appeared, and also no doubt some of it took up residence after moving from the display area. The display area when viewed at night with a torch is quite rich with little shrimps, snails and the like.

After about 6 months the surface of the DSB was a small sea of short waving tentacles, which belonged to small life forms trying to find food in their immediate area. In addition there were a lot of tiny shrimps running about - this was at night when viewed with a torch. In addition there were a few creatures, very small about ¼” (circa 6mm), which swam about, their eyeballs being picked out by the torchlight. The looked a little like brine shrimp but they were not.

This went on, with me feeding the DSB once weekly with small frozen fish pieces. When the fish went in the worms popped their heads up quite quickly, recognising that lunch had arrived.

The worms obviously lived in the sand, but I started wondering were the little shrimps etc lived. The DSB is flat - maybe they were in the sand too? Seemed a bit unlikely to me, but I never managed to track anything back to its lair.

I wondered if I could provide a better habitat for the tiny life. Therefore, 6 weeks ago, I placed some rock rubble at one end of the DSB. The rubble was that from the original rock that I had used to construct the reef - inert and very porous.

The rock is very light which is good, it won’t compact the DSB. The rubble pieces are around ½” to ¾” and form a light layer about 6″ wide and 8″ long. The major area of the DSB remains flat sand.

There has been a clear increase in the DSB population. The tiny shrimps have increased the most, and to a lesser extent so have the ’swimming eyeballs.’ Feeding the DSB has not been increased, so it seems that the noted increase in the population is down to the rubble that went in. So that was a success.

I have kept a watchful eye on the condition of the DSB throughout its life, and particularly after the rubble went in - I was watching for signs of compaction, that is, dark areas appearing in the sand below the rubble. There hasn’t been any indication of any problem.

Though the DSB may assist to an extent with seawater quality, there are two things that have occurred: first I have to make sure that when the grid to the pump area is open during maintenance a fish does not gain entry and eat any inhabitants. Second, when my wife is in bed quietly reading, sometimes I can be found sitting on the floor in the dark, face against the aquarium glass with torch in hand.

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Tags: Aquarium Filter, Aquarium Filtration, Aquarium Maintenance, deep-sand-bed, dsb, Equipment

I’ve Got Bio-Balls, Will I Be Ok?

No, no, you’ve got the wrong end of the stick! It’s not some horrible problem at all, but to do with aquariums.

Marine aquariums need bio-filtration, and this is provided by bacteria. The bacteria of course need a place to live and to avail oneself of this free service from nature the aquarist must provide them with a suitable home.

The bacteria operate what is called the Nitrogen Cycle, either fully or in part. To operate in part is easy, all that is required is plenty of oxygen plus ammonia and then nitrite. The bacteria will change the ammonia to nitrite, and then the nitrite will be changed to nitrate. Ammonia and nitrite are toxic, and nitrate much less so.

To support livestock it is enough to do only as in the previous paragraph. The toxic ammonia and nitrite are dealt with. Nitrate is left and this should not harm anything at very low levels.

However, the levels will slowly increase beyond the guideline (for a reef system) which is 10ppm (parts per million) or less. One way of reducing the level is with routine seawater changes. These changes are good for other reasons and should be completed, however nitrate could increase in spite of them. Nitrate increases are not desirable as the appearance of nuisance algae may occur.

Nature has a remedy but it cannot occur where there is oxygen present in any normal amount. The bacteria that reduce nitrate need an environment that is very low in oxygen - this forces the bacteria to extract oxygen from the nitrate thus removing it (it converts to gas and escapes the aquarium).

So bio-balls are a good medium for oxygen hungry bacteria, but not for bacteria that deal with nitrate.

If nature is going to assist with nitrate reduction, a denitrator (a so-called nitrate ’reactor’) could be used. Better, live rock can be used. Live rock has surfaces that can be used by oxygen needing bacteria, and well inside are areas for the nitrate bacteria. Live rock with a DSB (deep sand bed) is even better.

So if an aquarist is using bio-balls the answer is yes, it will be all right, except that the bacteria will produce nitrate and that will be the end of nature’s assistance.

If bio-balls are in use in addition to sufficient live rock (and perhaps a DSB) then the bio-balls can be removed, but remove them a few at a time over a period of weeks. This will allow any bio-load that was supported by the balls to be taken up gradually by the other media.

If the bio-balls were the only media, then none must be removed straightaway. Introduce sufficient live rock into the aquarium, wait a week or two, then commence removing the bio-balls a few at a time as already described. It would be of little use introducing, say, a canister filter for bio-filtration as the end product is the same - nitrate.

A good few years ago bio-filtration methods included balls. Times have changed.

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Tags: Aquarium Filter, Aquarium Filtration, deep-sand-bed, live-rock, nitrate, nitrogen cycle

Caulerpa

Mention the word ‘algae’ to a marine aquarist and the aquarist’s face might turn white, before he or she spins round to look at their aquarium and ask, in a panicky voice, ‘Where?’

We are all aware of that concern: nuisance algae! The stuff that covers everything in long thin strands of green or covers with a thin sheet of dark red or black looking film. Nuisance algae can be combated or avoided in the first place. But this isn’t about nuisance algae.

This is about nice algae for the aquarium! In the marine world there are a lot of types of algae that could come under the word ‘nice.’ They are decorative and sort after. Aquarists who use live rock may have been fortunate to see some grow.

Of course there is one algae that is essential, and this is the single celled type called zooxanthellae, or symbiotic algae, which dwells in the flesh of corals.

The algae here is Caulerpa sp. This is green, though the shade of green can vary, and generally grows longish leaves (sometimes up to 12″) which have various ‘patterns.’ The algae spreads by putting out runners, from the top of which the leaves appear. Underneath are holdfasts, which look a little like roots. The roots are simply anchors, however, as the caulerpa feeds through the leaves. This macro algae is very useful to the marine aquarist for decorative and/or filtration purposes.

A great deal could be written but all that will be done is a general description of the main types and what they could be used for.

The first and probably best known is Caulerpa prolifera. The leaves are plain and have straight edges which taper to a point. The leaves are normally flat. Growth is fairly speedy.

Two more attractive types are Caulerpa mexicana and Caulerpa seratuloides. They both have leaves that look a little like bird feathers, with individual sections sprouting from the stalk sideways on both sides from bottom to tip. These types could show rapid growth.

A different appearance from the previous types is Caulerpa racemosa. It is often called grape caulerpa because of the appearance: the leaves are bunches of small grape-like growths attached to the stalks. This type is more slow growing and more difficult to cultivate successfully.

What can be done with caulerpa? For decorative purposes it would of course be in the display aquarium, where it can look very attractive. However, the aquarist must be sure it doesn’t outgrow its welcome as some can spread rapidly. I had some Caulerpa mexicana in a previous aquarium and it was certainly attractive, though I had to harvest it regularly to maintain control.

The other area that caulerpa is often found is in a sump. Aquarists grow it there so that it can act as a filter. As it is an algae, it uses the same nutrients that nuisance algae does, that is nitrate and phosphate. In doing so it robs any potential nuisance algae of food. Even if hobby test kits indicate zero (undetectable) for nitrate and phosphate, it could well be that there is a low presence. Planting a piece of caulerpa and watching to see if it grows is possibly an indicator. Obviously, algae in a display aquarium will also reduce nutrients.

As with all plants caulerpa needs light. Fluorescent tubes such as T5’s or metal halide bulbs should be fine, so growth in a display aquarium should not be a problem as far as this is concerned.

Caulerpa grown in a sump can be lit a little differently. A fluorescent light with reflector will suffice, the light is usually quite close to the seawater surface. There may be an advantage in using a tube that has a K (Kelvin) value that is lower than normal for a display aquarium, such as 6500K. Or a white marine type can be used, around 10000K. In addition there are two ways of timing the ‘light on’ period. First is to leave the light on all the time without any dark period, which doesn’t seem to have any detrimental effect on the caulerpa, and the second is to have the light on period when the display aquarium is in the light off period. The second option could assist with pH stability - pH could fall a little when the display is in the dark period, but with the caulerpa lit this is counteracted.

When planting in a display aquarium, try the type of choice and see if there is any success. If not, try another type. In the sump, it could be a good idea to plant more than one type and see which ’takes’ first.

Caulerpa should be harvested from time to time, always leaving plenty to continue growth. As the plant uses nutrients, removing the caulerpa in a controlled manner also exports nutrients.

The aquarist may find that the caulerpa in the display aquarium is disappearing. Have a look at algae loving fish such as surgeons and rabbit fish - they could be fat and very happy!

Important Note: Caulerpa in the aquarium is fine, decorative and useful. However, when harvesting, or simply removing caulerpa of any type it must not be thrown away into the sea. Caulerpa is invasive and can and is causing problems.

In some areas caulerpa is banned because of problems. Please check the position in your area before obtaining caulerpa.

For some information here is a link:

http://www.sccat.net/#the-caulerpa-information-center-1e86c5

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Tags: Algae, Aquarium Filtration, Aquarium Lighting, caulerpa, deep-sand-bed, refugium

Can Tonga Live Rock Provide Enough Filtration?

Live rock as has been said time and time again is a phenomenal filtration medium. There are various different types of live rock available all of which provide the required filtration to the aquarium if enough is placed into the aquarium.

There is one in particular however that in my opinion is more decorative and ’standard’ live rock.

Tonga rock

Tonga rock is different to other types of live rock due to the reason that it looks like branches of a tree. It can be an extremely decorative addition to a saltwater aquarium. Due to tonga rock being thinner and not boulder shaped like the majority of other live rock with the obvious exception of plating rock you have the ability to be able to create fantastic water movement around it.

In my opinion tonga rock is fantastic for SPS corals as you can provide a large amount of water movement and if carefully aquascaped can look amazing. This is not to say that you could not have a fish only aquarium or a soft coral aquarium with tonga rock as you would be able to. You would just have to bear in mind that you will need to create caves etc for the fish to hide in as well as creating ledges to place the soft corals on.

But what about the filtration - is tonga rock as good as other live rock.

Tonga rock does have good filtration capabilities however they are not as good as other live rock. This is mainly due to the size of the physical rock. To purchase enough tonga rock to faciliate the filtration requirement would make it very hard to aquascape.

So what do you do?

In my opinion it is quite simple. I personally would use the tonga rock for decorative purposes and then have an in tank deep sand bed as well. The deep sand bed would be the main aspect of the filtration but the tonga rock would do some as well albeit reduced. You do not need to have the deep sand bed in the display aquarium it could be in the sump in the cabinet. You would just need to make sure that the partiton designed for the deep sand bed was large enough.

One of my dream aquariums (we all have them don’t we) is to have a 3 foot cube tank (3*3*3). In this aquarium a deep sand bed would be placed and tonga rock used for decorative purposes as well as some plating rock to provide some hiding places/ledges. Lighting would be provided by metal halides, the water movement would be chaotic and my corals of choice would be SPS with a small amount of fish.

We can but dream can’t we?

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Tags: Aquarium Filter, Aquarium Filtration, Care, deep-sand-bed, live-rock, refugium

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