First Introduction - Fish Or Invertebrate

The majority of aquarists decide that the first introduction to their aquariums should be a fish yet does it need to be this way.

I fully understand why this happens and perhaps this is due to historic reasons where aquarists used hardy fish to assist in the cycling of their aquariums. Something which I am glad to say is not done anymore. Perhaps it is the movement and colour of the fish which draws the eye. There are many reasons as to why people choose a fish as the first inhabitant of their aquarium. It uis of course not up to me to sway their decision in any way but perhaps people believe that a fish has to be the first introduction.

On another note if the aquarium is a fish only aquarium then the aquarists will of course be introducing a fish first!

For the aquarist with a reef aquarium however there is another choice especially when live rock is used as the filtration but it does not matter what filtration is employed. Live rock even when matured correctly is not very sterile and therefore may carry opportunistic parasites. When a fish is caught in the dealers it is put under immense stress due to the catching, the bagging, the transport etc. When the fish is introduced to the aquarium its immune system may be lower than normal and in a reef tank filtered via live rock it may become prey to opportunistic parasites.

I appreciate that the above can happen at any time in the aquariums life however at the very start the aquarist is learning and if a fish is lost at the very start then this is sad for obvious reasons however the aquarist’s confidence in the aquarium and his/her own abilities and may give up the hobby.
There are certain fish which are more resilient than others however a lot of these fish - damselfish for example can become problematic later due to the aggressive nature and it is very hard to remove a fish from an aquarium with live rock in it!

Another method at the very start instead of fish is introducing hardy invertebrates.

By introducing hardy invertebrates first the aquarist will gain experience in acclimatisation techniques as well as stocking techniques. At the very start when the aquarist’s knowledge is low for want of a better word it is probably fair to say that a fair amount of tinkering will be employed. What I mean by this is that the aquarists hands will be in the aquarium a lot moving various corals around as well as the relevant water movement devices until they are satisfied that the conditions provided in the aquarium are suitable for the aquarium inhabitants.

If the decision is made to introduce invertebrates prior to fish then the aquarium, as with fish must be ready for the introduction of them. By this I mean that the nitrogen cycle has completed, there are no large algae outbreaks evident or they are under control and the water conditions are maintained in accordance with the recommended levels. For examples nitrates should be low as should phosphate levels. More than that the water conditions should not just be maintained they should be stable.

With the aquarist deciding to introduce invertebrates in the first instance the equipment purchased and installed should be capable of support the life in the aquarium. For example the lighting needs to be correct. This may sound basic but I hear of a lot of people trying to keep corals under lighting which to be honest is just not suitable for them.

At this point - actually a lot earlier the aquarist should know what corals, fish etc that they want to keep and should have based their purchases around this decision. At this point in the aquariums life you would not be looking at introducing an SPS coral like acropora etc as the aquarium is simply not ready for it.

At this point the corals you will be interested in purchasing are the ones which are not too expensive and do not have the colour of the majority of SPS corals. This is not to say that these corals are dull and colourless as they are far from it but when you compare prices you will see what I mean!

Speaking of purchase again I recommend that you build a relationship with a local dealer, another hobbyist or an online area (like Aquarists Online hint hint…) where you can go and ask advice as to what is suitable etc. Building a relationship with others is important as you can use their experience, their knowledge to your advantage o=plus you can learn a lot about the hobby and will hopefully not make expensive mistakes.

When selecting corals you are looking for corals which are suitable for the beginner. When looking you will probably see some exceptionally colourful species. I would probably stay away from these as there are some species which do not contain zooanthellae and require feeding for them to thrive. A good example of this is the sun coral. There are also other colourful ones which are probably for more advanced aquarists or aquarists who have had stable aquariums for a long period of time.

You have to remember that the aquarium is new and the water, rockwork, sand, glass, equipment etc all needs to age. You can always come back to these more colourful corals when your confidence has grown by maintaining a reef aquarium for a number of years.

In my opinion the list below details what I believe to be good ‘starter corals’ and are suitable for first introduction.

• Button Polyps
• Xenia
• Mushrooms
• Leather Corals
• Star Polyps

This does not mean that you should not introduce fish. I personally think that an aquarium with just corals in and no fish lacks movement however I think that perhaps more aquarists should introduce invertebrates prior to introducing fish to gain both confidence in themselves as well as giving the aquarium time to settle.

This of course also does not mean that you will not get problems when introducing fish at a later stage. You might but just remember to acclimatise them properly and use a quarantine tank.

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Tags: Aquarium Filter, Care, Equipment, invertebrate, live-rock, nitrogen cycle

Understand The Nitrogen Cycle - Your Livestock Depend On It

Modern reef aquariums try to be as natural as possible. The modern day captive reef would make yesterdays marine aquarists eyes water - they are so beautiful in total and in detail. Fish only systems house fish that would have been impossible to keep not that long ago. This success is because of natural processes and modern technology.

Whatever type of marine aquarium is kept, reef system or fish only system, there is one function that is totally essential. It isn’t a modern natural ‘invention’ either, it applied to those earlier aquarists just as much. The difference is that in the very early days the aquarists didn’t know anything about it. Before my time a pioneer marine aquarist thought he could keep his aquarium clean more easily by using what turned later into the much used under gravel-filter. I believe his name was Straughan. He was amazed about the length of time he was able to keep livestock, and put it down to better cleanliness. Investigations showed that in fact he had stumbled onto the secret of keeping any marine system basically healthy. In a way it was due to better cleanliness.

Livestock in an aquarium continue with their normal life functions. They are fed. Algae can die and rot as can uneaten food. This protein breaks down into a deadly toxin - ammonia. In the presence of not a great amount of ammonia livestock can be badly affected or die. Fish could hang quietly at the water surface, or swim in a very erratic manner, even upside down, or sit on the aquarium bottom leaning against a rock, and breathing could be rapid. This situation is very serious.

Yet in the modern aquarium the problem of toxins hardly arises, except perhaps in the case of a beginner who does not use patience and stocks too rapidly.

The saviours and the servants of the aquarist are bacteria. These bacteria break down toxins and the process is generally known as the nitrogen cycle.

Ammonia is very toxic and is broken down by bacteria called Nitrosomonas. The toxic ammonia is converted to nitrite, which is also toxic and nearly as bad as ammonia. That’s a lot of good! Well, another bacteria then comes into play and converts the nitrite into nitrate. These bacteria are called Nitrobacter. Nitrate can be bad at high levels, but is safe in comparison to ammonia and nitrite. The nitrogen cycle does not stop at this point, but continues when the nitrate is converted to nitrogen gas. The gas escapes from the aquarium and the cycle is complete.

Simple, nature saves the day!

Yes, it does, but there has to be a catch and here it is - the ammonia/nitrite conversion bacteria need a different environment to the nitrate bacteria.

The ammonia/nitrite bacteria require an environment that provides obviously ammonia and nitrite, and in addition they need a good supply of oxygen. This oxygen can only come from the water (except in one instance) so the aquarist has to provide plenty of water circulation to ensure good gas exchange at air/water interfaces such as the surface of the seawater. The home for the oxygen hungry bacteria can be in a canister filter and the like with suitable media. What is the exception mentioned - this is the so-called trickle filter. As the seawater running down is exposed to the air, oxygen is plentiful.

Providing a suitable home for the ammonia and nitrite bacteria is easy. The aquarist needs to ensure that the canister etc filters are properly matured, and this is achieved by using a prepared commercial maturation fluid. Using test kits, once the nitrite has disappeared the filter is initially mature. The instructions with the fluid will give details which are very straightforward. The nitrite showing as cleared means that there is a presence of bacteria which will deal with ammonia and nitrite. When the filter is initially mature, stocking can commence, but with great care and patience, as the filter is still unstable and needs to adjust to the bio load placed upon it.

The problem - here we go again - with canister etc filters is that the complete nitrogen cycle is not achieved. This is because they operate in an oxygen rich environment. Bacteria that deal with nitrate can live in an oxygen rich environment too, but under this circumstance they will not deal with the nitrate. An environment must be created where there is a lack of oxygen, and in this circumstance the bacteria will turn to the nitrate. The bacteria need oxygen, and the only way they can obtain it is to extract it from the nitrate, which breaks the nitrate down.

So there is no reason why a marine system cannot use a canister etc filter. It does mean though that the aquarist must keep a careful watch on nitrate levels as well as other parameters. Routine seawater changes will control nitrate to a degree, as will good husbandry such as a proper feeding discipline. There are other ways to control nitrates which will not be dealt with here.

There is a way of achieving the full nitrogen cycle, and that is to use live rock. This live rock (LR) can be used in fish only and reef aquariums. In the reef aquarium it has the secondary benefit of providing a material with which to construct the reef.

LR works as filtration because it is porous and provides a home for the bacteria. On the surface and inside toward the surface dwell the bacteria that use oxygen and deal with ammonia and nitrite. Deeper inside, where oxygen levels are depleted, dwell the bacteria that can only obtain oxygen from nitrate. Therefore the total nitrogen cycle is achievable. It is important that sufficient live rock of good quality is provided.

Using LR the aquarist still needs to monitor seawater parameters. Nitrate is included in those parameters, as LR has limits the same as anything else. That said, it is a wonderful filtration media.

Whatever type of bio filtration the aquarist uses, the bacteria will not make many demands, and the demands they do make are easily met. Fail to meet those demands, or pass the point where the bacteria do not have the capacity to deal with toxics, and the consequences could be very serious.

Provide suitable media and well oxygenated seawater, have patience with stocking and do not overstock, and nature’s bacteria will work silently and unseen providing life support.

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Tags: Aquarium Filter, Aquarium Filtration, Aquarium Water, Care, nitrogen cycle, Water Quality

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

The Bacteria’s Role In The Nitrogen Cycle

In the marine aquarium, be it a reef tank or a fish only aquarium, the nitrogen cycle is of paramount importance. It is the life support function for all the livestock. Without it, or with a serious deficiency, the livestock will be in serious difficulty and face death.

In an aquarium the livestock carry on with their normal life functions and need feeding. This introduces waste into the seawater. In addition, algae etc can die and rot. The product of the breakdown is ammonium (NH4+). Because seawater is at a fairly high pH (around 8.3) some of this ammonium is present in the form of ammonia (NH3). That is the problem, ammonia.

Ammonia that is present even in small amounts is toxic - deadly - to aquatic life. Fish can display ammonia poisoning by peculiar swimming: Swimming slowly and rolling over, going up and down in a random fashion, breathing very quickly, lying at the bottom, floating around at the top etc. Varied, but if seen there can be no doubt something is wrong. If only one fish is behaving strangely, and the rest are normal, the problem is unlikely to be ammonia poisoning.

Nature is ready to deal with the problem, luckily for us aquarists. There always seems to be some kind of life that is ready to use up whatever is available, and with ammonia this is the case. The life forms are Nitrosomonas bacteria. The ammonia is used by the bacteria for energy.

So that’s fine then, problem solved. Not quite. Even though the bacteria mentioned have removed ammonia, it hasn’t been conjured into oblivion. Guess what, the ammonia has been converted to nitrite (NO2) which is nearly as toxic as ammonia. Fish reaction to nitrite is similar to ammonia.

So what we have is a cycle, as in the heading. More bacteria use the nitrite, these bacteria being Nitrobacter. The situation becomes much better after this stage, as the product produced is nitrate (NO3). This is nowhere near as toxic as ammonia and nitrite, but can cause some problems at high levels. Probably the major problem that aquarists could face with nitrate at lesser levels is excessive algae presence.

Nature however can once again come to the aquarist’s aid because, yes that’s right, bacteria can deal with the nitrate. Hang on a moment though, there’s a qualification here. It depends on the bio-filtration being used (the bio-filtration is home to the different bacteria). If the aquarist is using live rock, fine, good quality live rock in proper quantity will deal within reason with nitrate. If the bio-filter is a canister, for example, then there aren’t any bacteria present to deal with the nitrate. Why? Because the environment is oxygen rich. To deal with nitrate a nil to low oxygen environment is required. Live rock can provide this as the bacteria involved live deep inside. If the example a canister filter is in use then other means are available if required to control the nitrate.

The nitrate is removed because the bacteria extract oxygen from it, this being the only way open to them. The end gas, nitrogen, is released from the seawater at air/water interfaces.

So the whole nitrogen cycle is from ammonia to nitrogen gas. There are several ways to achieve the cycle, but whatever method is chosen (except perhaps one) there are important points for the aquarist to be aware of.

The bacteria colonies that convert ammonia to nitrite use a lot of oxygen in the process. The next stage, nitrite to nitrate, uses up a lesser amount. There is only one place that the oxygen can come from and that is the seawater. In addition to the bacteria, the reef livestock need oxygen in good quantity. So the seawater must always have a good oxygen content. Having said that, the modern reef or fish only system usually hasn’t a problem, as they are mainly open topped, often use weirs, and have good water circulation, particularly reefs. If oxygen content were ‘near the edge,’ it could be more of a problem for a fish only system because of the usually higher fish stocks per gallon. What is the possible exception mentioned in the previous paragraph? The trickle filter. Seawater is exposed to the air as it runs down through the media, which means oxygen from the air could be used (an air/water interface).

The nitrogen cycle bacteria are not present instantly. With ‘unnatural’ filters, such as the example a canister, they are introduced by inoculating the seawater with the required substances. Commercial preparations are available. Measuring the seawater for ammonia, nitrite and nitrate advises the aquarist when the bacteria colonies are working. Live rock is different, as the required colonies of bacteria should be present. Caution still has to be exercised as these colonies might have been diminished in the ocean to aquarium processes.

There isn’t any argument - the life support system, or bio-filter, or nitrogen cycle, call it whatever, must be present and effective. It will then protect the livestock by working unseen and silently.

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Tags: aquarium, Aquarium Filter, Aquarium Filtration, Equipment, live-rock, nitrogen cycle