Life Span Of Tropical Marine Fish

We look after our fish very well, don’t we. Whether it is a fish only aquarium or reef aquarium, a lot of thought goes into choice, taking into account compatibility, size and character. All in all, the fish should be healthy and happy.

The marine aquarium is a stable environment (or should be) with all the parameters at their proper levels. The fish receive a varied and appropriate diet. There is little stress I would imagine, apart from the odd squabble that usually doesn’t amount to much. Predation doesn’t exist.

On the wild reef the fish are more stressed as they hunt for food, attempt to avoid becoming food, maybe defend a territory, ensure they have a safe haven for the night and additionally have the need to breed.

Disease is a threat in both environments, but more so in the aquarium. The aquarium gallonage is really miniscule compared to the enormous gallonage of the reef, so the appearance of disease is much more serious. Just consider the entry of oodinium. The fish in the wild may meet it once or twice or not at all. If it does appear it is unlikely to cause a problem. So disease is an area where captive fish could be more stressed than their wild counterparts.

So the lifespan of fish that are commonly kept in captivity is easy to record. All that is required is for the aquarist to note the date when the fish arrived at his/her aquarium. My fish have dates recorded - for example, the flame angel (Centropyge loricula) is 5¾ years old. This excludes the period in transit and with the retailer of course.

Knowing the real age of a fish is close to impossible. How long has the fish been in the wild? Who knows, maybe there is a size related calculation that could assist? But size relates to diet and overall health to a considerable degree.

Perhaps a comparison could be made between wild and captive fish. The fish selected would have to be of the same type and of the same size. So taking the flame angel, it is easy to note the date the fish entered an aquarium, but the fish in the wild would have to be tagged or similar, and how would track of it be kept? No, it isn’t going to happen.

So the only lifespan that could be measured would be of fish in an aquarium. That would not reflect the potential real lifespan, of course, as there are many variables and a lot of the variables have changed.

An inquisitive aquarist keeping fish in captivity will just have to refer to a record and state to a fellow aquarist with pride ‘I’ve had this fish for x years.’

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Tags: aquarium, aquarium-fish, marine-aquarium, marine-fish, reef-fish, saltwater-aquarium

The Banggai Cardinal

The Banggai Cardinal, proper name Pterapogon kauderni, is a relatively new fish for the salt water aquarium. The fish in the aquarium is fairly sedentary, but has lovely colouring with black vertical striping on a silver body. The tail is long and forked, again being silver/black. It has become popular and can now be seen in many home aquariums.

I became concerned about this lovely fish as I thought there was a danger that supplies of the fish from the wild would dry up. Then I learned something potentially much more serious - perhaps wild stocks were in jeopardy which made my initial feeling insignificant.

As far as supplies drying up, this isn’t going to happen. First, the fish in captivity is much more helpful than many marine species in that it brings its young into the world much like a freshwater cichlid - it is a mouth brooder. Eventually the young require a defence and this is easily supplied with real sea urchins, the long spine types, or something artificial which is similar and quite easy to accomplish. So some pressure on wild stock is eased a little in that way. Only a little though, as the fish can only produce a few young in each batch. Clownfish, for example, produce far more young. But at least breeding is an option.

The second concern about wild stocks being in jeopardy as said is much more serious. It is estimated (on what basis I don’t know) that circa 700,000 of these fish is collected for the aquarium trade every year. The total population is thought to be in the region of 2,000,000. It doesn’t need a mathematician to work out that the collection ratio is high. The fish come from one small area in the Pacific Ocean and therefore is not widespread.

A proposition had been put to CITES to ban totally the collection of this fish, on the basis that the population could not be sustained with such a high collection ratio. This ban would mean that US and EU imports would cease, though presumably captive breeding would mean the fish would remain available but at a very much increased price.

However, in deliberations CITES have not imposed a ban. This is because the government of the area has agreed to a strict management programme which is to include training of local collectors and the number of fish that can be collected in view of the estimated populations. The aquatic trade is involved, and monitoring is to be carried out by an independent authority. CITES has accepted the fish is at risk, but, as said, have not banned collection.

This is good for the marine hobby. The fish will still be imported, but in smaller numbers, and the number available to the hobby boosted by commercial and private breeding programmes. The local collectors still have their income, or part of it, protected as far as possible. Above all, it appears a commonsense outcome in this day and age when there are many pressures, sometimes misinformed, to ban ‘exploitation’ of the wild.

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Tags: aquarium, aquarium-fish, Coral Reef, marine-aquarium, marine-fish, reef-fish

I’ve Heard Of The Cleaner Shrimp But What Is The Cleaner Fish?

I would imagine that all marine aquarists have heard of, and probably seen, the cleaner shrimp (Lysmata amboinensis). This colourful shrimp is very popular, becoming used to the aquarist very quickly and even walking around on the hand if the opportunity presents itself - a large and strangely shaped fish to be cleaned perhaps.

There is another creature known for the natural cleaning activities it undertakes. This is the cleaner wrasse (Labroides dimidiatus). The fish is commonly known as the cleaner wrasse or blue streak wrasse. There are other reef fish that undertake cleaning duties particularly when juvenile, but this wrasse does it as a full time job.

The wrasse likes to go into a small hole or crevice for security when night arrives. During the day, it seldom moves far from the area, as it is a cleaning station. In other words, the little wrasse, usually in a group, wait for other fish to come so that they can be cleared of parasites and other irritants. The wrasse goes busily about the fish being cleaned, as this is the food source. They will even enter the mouths and gills of bigger fish, including predators - the larger fish normally hang still, fins spread when being cleaned, and keep their mouths open to allow easy access. The cleaner wrasse are protected from predation during this activity possibly by their swimming motion, colours, shape, or all three. The cleaner stations are well known to other reef inhabitants, and it is known for fish to wait and queue patiently for attention. There are always enough fish for cleaning, and thus food for the wrasse.

As with many wrasse, the cleaner is hardy in a good aquarium environment. It needs plenty of swimming space and places to hide. The normal caution should be exercised with regard to health when purchasing one.

On the wild reef there are plenty of fish to be cleaned, but not so in the aquarium. Even in a fish only system where there are normally more fish per gallon, there is insufficient natural food. It follows that this will be the same in a reef system. Also of course, the last thing the aquarist wants is parasites in the aquarium. Talking of parasites, it might be thought that the wrasse could be of use in a fight against marine white spot or velvet. Unfortunately, this is reportedly not the case and the wrasse is vulnerable to the parasites as well.

When considering introducing a cleaner wrasse to the aquarium, the usual compatibility question applies, though this is not usually a problem from the wrasse‘s point of view. When the wrasse is in the aquarium, natural instincts continue. It may ‘think’ that the fish in the area are waiting for cleaning and attempt to carry out this task. These attempts can continue over and over again, day after day, and other fish can be highly irritated by the attention. The wrasse may be repeatedly warned off, though it is unlikely to be attacked, though if the system is a fish only with predators there could be a problem. Some predators, such as lionfish, may not have very good manners! It is said that if the wrasse ‘learns’ when food is available and responds to it with the other fish, the cleaning drive could diminish, as the driving force, hunger, is reduced.

As with other fish it is a good idea to ask a retailer to put a little food in the aquarium and watch the response of the wrasse. Many wrasse are easy to feed, generally being gluttons, and the cleaner type is reported to feed well too. There have been reports of starved cleaners that perished, but this does not appear to be the norm.

The food fed needs to have a little resemblance to that in the wild. Fortunately, most other fish will take it as well. Try frozen foods that are prepared for marines, such as mysis shrimp, artemia, shellfish, squid, lobster eggs and the like. Some may need to be chopped so that the cleaner can handle them. It is reported that the fish will often take flake food. A diet with plenty of variety, plus flake if possible, should be successful. Fed carefully, the seawater conditions should not deteriorate as other fish present will eat the same diet.

On the wild reef mimicry is not unknown, and so it is with the cleaner wrasse. Other fish trust the wrasse and do not hesitate to present themselves for cleaning. Taking advantage of this is a fish which is closely coloured and patterned. This is the false cleaner (Aspidontus taeniatus), which in fact is a blenny. What it does is present itself to a fish which is ready for cleaning, but instead of being useful it quickly bites a bit of fin or scale and dashes off. Not the way to win fishy friends! It is unlikely to be obtained in mistake for a proper cleaner, but the two are easily identifiable, the proper cleaner has a mouth at the front of the fish, the false one has an underslung mouth.

There are other cleaner wrasse, but none are reported to take to aquarium food as readily (I’d better avoid the word ‘easily‘) as the one discussed.

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Tags: aquarium, home-aquarium, marine-aquarium, marine-fish, saltwater-aquarium, saltwater-fish

If A Fish Dies Should You Remove It From The Aquarium?

The loss of a fish is a very sad occasion and often, whether the cause is known or not, the aquarist will wonder if it was his/her fault. Most (all?) aquarists lose a fish occasionally when the rest are perfectly healthy.

Despite the sadness, the aquarist needs to take action to maintain the quality conditions inside the aquarium, which will protect other livestock from further problems. A rotting fish may cause a rise in the load on the bio-filter, and the bio-filter may not be able to cope.

The answer is yes, the fish should be removed if possible. Easy enough maybe, unless there are many rocks in the aquarium. Fish often have a tendency, probably a defence mechanism, to hide in rocks when there is a problem.

In a fish only system using an external filter and not a lot of rock, or even one which uses a good quantity of live rock, as there aren’t any corals it should be practical to move rocks about until the corpse is discovered. This will stress the remaining fish and therefore the rock movement should be minimised as far as possible by moving rocks and replacing them in a methodical manner until the corpse is found.. This should also preserve the layout of the rocks. On the other hand, the ‘fish only with live rock’ aquarist if necessary could leave the fish in the rocks and proceed as in the reef system below.

In a reef system it is more difficult. The reef is constructed of many rocks and is usually covered in may corals of various types. The aquarist is not going to be particularly keen on dismantling the reef, even if it can be done methodically. The disruption is greater, and the stress to the living fish would probably be more severe. So what is the procedure?

It is the water quality that is being watched. As said, the presence of a rotting corpse can stretch or overload a bio-filter. The reef aquarist could make the decision to ignore the dead fish and monitor the water quality. This is an option because in the reef system there are normally less fish, again to protect water quality (though the bio filtration mechanism will still have adapted to the load it has to deal with). What is being daily tested for is any presence of ammonia. At the same time, the actions of the fish should be watched to ensure they are not showing any sign of discomfort, such as increased breathing rates and/or erratic and unusual swimming. The corals too should remain as normal. If any problem does appear then the action is a water change to dilute the toxin, the amount depending on the severity of the problem.

That said, it is possible that the reef aquarist will not note any detrimental changes in water quality, particularly in a mature reef. This is because the many tiny occupants of the reef are always ready for a meal, and are perfectly able to dispose of a corpse. I have, over the years, lost fish and removed them from fish only systems, and left them alone in a reef. The reef life dealt with the problem and removal of the fish in the fish only system prevented any problem arising.

The loss of a fish calls for water quality checks, unless the aquarist is sure of the cause.
If the fish can be removed, it is best to remove it. If not, monitoring the water quality for say at least a week should provide an adequate safeguard.

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Tags: captive-fish, marine-aquarium, marine-fish, saltwater-aquarium, saltwater-fish

Consider Tank Raised Marine Fish

There are a lot of people who decide to start a marine aquarium due to seeing a natural coral reef in person, on televsion, in pictures etc.

Of course there are lots of other reasons as to why people start saltwater aquariums.

But that’s not the purpose of this post.

The majority of aquarists have a passion for life in the wild as well as the life which they keep in their home aquarium.

And rightly so - life in nature is wonderful.

This does however bring an issue to ‘us aquarists’

We love the life in the ocean yet we need to remove some of this life so that it can exist in our home aquarium.

Granted a lot of the fish, corals etc on the reef are monitored and protected so that the reef is not drained empty of life yet we as the responsible aquarists we are need to at least try to do our bit.

By that I mean considering purchasing tank raised marine fish.

For those who are not sure what a tank raised fish is let me enlighten you. Basically they are marine fish which are bred in an aquarium and allowed to grow until they are old enough to be made for sale.

So what’s the beneift.

Two fold really. The first is that with them being tank raised they have not been removed from the wild, therefore the populations in the wild are not reduced. Secondly they are generally hardier than wild fish so are more accustomed to life confined to the aquarium.

To me that is two good reasons to at least consider it.

A while ago we were very limited to what we could purchase in this area however nowadays the selection is much greater.

You can purchase fish such as :

• Clownfish
• Dottyback
• Banggai Cardinal
• Gobies
• and more…

Don’t worry if your local fish shop do not have any in stock. Just ask and I am sure that they will be able to acquire some for you.

Maybe you will not fill your entire aquarium with tank raised marine fish but if you at least have a couple then you have helped to reduce the impact on the wild reef.

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Tags: captive-fish, marine-aquarium, marine-fish, saltwater-aquarium, saltwater-fish

Excitement With A Sad End

Many years ago, when I was fairly new at the marine hobby, I was really overcome with excitement. I had a fish only system at the time, the move to a captive reef was yet to come.

So what was all the excitement about? I had seen and ordered to be kept for me a juvenile emperor angel (Pomacanthus imperator). This 3″ or so beauty was cruising up and down the dealer’s show tank, looked in full health, and could not be resisted. I did some research in the dealer’s shop using a book that he provided. It was fully compatible with my aquarium stock and the aquarium was quite large enough.

The juvenile emperor has a blue body with a series of white rings and is most definitely beautiful. This colouring is lost as the fish ages and it turns into beautiful nearly horizontal narrow yellow stripes interspaced with blue. The top of the fish’s body is yellow and the bottom dark blue, with a yellow tail. Perhaps the most striking is the white mouth area, with the eyes covered in dark blue - this gives the fish a very ’cool dude’ appearance. The full adult size is about 12”. Why there is this colour difference between juvenile and adult is open to speculation. It has been said that perhaps the juvenile colouring protects the fish from the attention of the territorial adults.

Anyway, an aquarium that had contained two clowns was prepared so it could act as a quarantine tank. The fish was carefully introduced to this temporary accommodation and the lights left off. In a day it was noticed to be eating some red algae that was growing on the rocks. A small amount of flake was offered which the fish took without problem. The fish fed from day two without problem, on any fishy food offered, including blanched lettuce.

After two weeks the fish was transferred to the main display aquarium. There wasn’t any problem at all, the fish swam out of the bowl it had been transferred in and cruised regally up and down its new home. All areas of the aquarium were checked by the fish and it was completely settled. The other fish had no real interest in the newcomer apart from a little caution, probably because of the newcomer’s size (the other inhabitants were smaller).

The fish lived for many months quite happily. It fed well, rising with the other fish to the fingers. Dietary needs were met.

One day, oh, I remember it so well, I went to the aquarium to see the fish and in particular my ’special’, and it was very slowly moving along the bottom of the aquarium. The other fish were fine. I put my hand near the glass and the fish did not respond, though the others did. Hoping there wasn’t anything wrong, I waited. I couldn’t see anything wrong with the fish itself.

The fish didn’t improve. Water testing followed, there was nothing wrong. By this time the fish was laying upright against the front corner of the aquarium, not swimming at all. Breathing was quite slow and as it had always been. I looked at the fish closely but could see nothing wrong. There were no torn fins, damaged areas of the body, or cloudy eyes. I got a magnifying glass and looked closely at the fish, but couldn’t see any of those dreaded tell-tale signs of marine velvet or white spot. The fish did not improve.

Clutching at straws, I did a water change with carefully matched SG and temperature. I then dosed the tank very carefully with a copper medication. Though this is effective for some problems, no medications should be given for the sake of it. The copper dose was maintained carefully and none of the fish showed any stress, including the emperor which did not improve. The other fish were eating, but not the emperor.

After a few days (I didn’t record the exact number, it was around 7 to 10) activated carbon was added to clear the copper, followed by another water change. The emperor had moved a little, it was now leaning against the middle of the viewing glass.

I don’t know why, but I had the sinking feeling that the next day the emperor would be gone. I remember that feeling! The next morning I went to the tank and the emperor was still in the same position. It was dead.

I felt guilty for quite a long time, and no-one I spoke to could give me any clue as to why the loss had occurred.

Thinking about it later, and even now, I think that I acted reasonably in the circumstances. As there wasn’t a clue to be seen on the fish of the cause of the problem, I have wondered if it was internal, a parasite perhaps. I will never know.

I cannot keep an emperor now, as first my current aquarium is too small and second the fish is not reef compatible. If I could, I’m sure an emperor would be among my livestock.

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Tags: home-aquarium, marine-aquarium, marine-fish, saltwater-aquarium, saltwater-fish

Remember To Vary The Food When Feeding

A fish only aquarium or reef aquarium offers several pleasures. One of them is obvious, and that is just sitting and admiring. After a while, all seems at peace in the world. Maybe that’s why some doctors and dentists have aquariums in their surgeries.

Another very pleasurable experience for the aquarist is feeding, probably because it is direct interaction. Once fish are accustomed to routines, they can nearly ’talk’ to the aquarist. ‘Feed Me!’ Not forgetting the cleaner shrimp walking around on the hand looking and hoping for a morsel.

Feeding obviously is important. Fuel is important to all living creatures including us aquarists - and I don’t mean just the beer!

What if we aquarists sat down to dinner each day and were faced with the same food repeatedly. Not too impressive really, and boring. Additionally, nutritionally we’d probably miss out on important vitamins and minerals too.

Fish and shrimps are the same. They have to eat, and if they are faced with the same food each day they’ll eat. However, no matter how good the food preparation is by the manufacturer, it is likely that it will not be fully balanced.

The first consideration is what type of creature it is - vegetarian, carnivore or just opportunist. Surgeon fish are a generally good example - they need algae and if there is insufficient in the aquarium it must be provided. So a base diet has to be provided if the fish have any particular demand.

My fish are omnivores, feeding from the substrate or water column. I have seen them eating algae but it is not an absolute must (the dwarf angel needs algae but not like a surgeonfish, and there is a little, and sufficient, algae in the aquarium). My base food is marine flake, which contains many ingredients suited to marine life and has additional vitamins and minerals added. The supplementary food I use is frozen, consisting of brine shrimp, mysis shrimp, lobster eggs, and chopped cockle. There are others available.

The fish are fed twice a day, although on occasional days I miss a feed, which clearly breaks the routine. On other days one feed is flake and the other is one of the frozen foods. The flake is usually fed in the evening and the frozen after the lights have been on a while, but now and again I change this round. The frozen food is kept in a separate sealed plastic sandwich box in the freezer. It is pre-prepared by taking one square from one of the food types and cutting it into four while frozen. These pieces go back in the box and are fed one at a time until the four pieces are gone. I then pick another type of frozen food and do it again. So the frozen food is varied. It would be just as easy to cut squares up from different types of frozen foods and feed them randomly. So the fish receive a basic diet and also a varying frozen one. In this way hopefully they receive an overall adequate diet which will keep them healthy. My fish have been in residence for 5+ years and have good health and colour. (There aren’t many fish as I have regard to the seawater quality.)

Another advantage of this type of feeding, particularly with frozen food, is that other life in the aquarium feeds too. When I feed the frozen varieties I see polyps catching some. Some goes into the rocks, as does some of the flake, and I am sure the myriad of tiny reef creatures enjoy it.

Talking of nutrition, remember to keep flake food containers tightly shut when not in use, and frozen foods properly frozen. When thawing food, do it in a small utensil. Do not put it in a microwave, but let it thaw naturally in either a little seawater or R/O (reverse osmosis) water.

Proper feeding helps maintain a healthy aquarium and healthy vigorous livestock. At this point I’m sure I’ll be forgiven if I state once again - don’t overfeed! There is an article on this site about feeding called ‘Feeding Time’, it comes under Care and Maintenance. I’ve put a link below.

http://www.aquaristsonline.com/articles

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Tags: Aquarium Maintenance, aquarium-fish-food, Care, feeding-fish, saltwater-aquarium

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