The Yellow Tang

This fish is one recognized by all marine aquarists; it is very popular and commonly kept. If a splash of colour is required then this is one of the fish to consider, it attracts the eye like a magnet does metal.

The fish is properly called Zebrasoma flavescens. It is yellow all over apart from a small white area in front of the tail; this is the ‘scalpel’.

The yellow tang could grow to 7½ inches (circa 19cm). As with all fish of this type it is not for every aquarist as swimming space is required. A small aquarium is not a home for it; a suggested minimum size is 3ft (circa 91.5cm) by 1.5ft (circa 45.75cm) by 1.5ft though larger is better. If the reef structure is large this will reduce the swimming space, so even if the aquarium itself seems large enough the actual free seawater space needs to be checked.

The yellow tang is reputedly one of the hardiest of the surgeon fishes. Of course high quality seawater needs to be provided at all times. Tank mates should be compatible though even so aggression could appear, but usually with needs properly met they are peaceable enough.

Feeding these fish is not difficult, they will usually take marine flake and de-frozen foods. However, it is essential that they receive adequate amounts of algae. In the aquarium some of this could be provided by natural growth and in this way the fish is useful in keeping algae down – it should eat filamentous algae. Aquarium algae are not normally present in sufficient quantity so the aquarist needs to provide the food in other ways. One of the best methods is to purchase sheets of dried algae such as Nori. One sheet or a part of it can be held in place by an aquarium clip and left. The fish should eat it enthusiastically. It is suggested that algae is fed at least every other day, though many aquarists place the food in the aquarium everyday to ensure the fish can take it at will – any sheet algae that breaks free should be re-fixed or removed and any uneaten after a full day removed.

Brightness and colour are usually present in a marine aquarium and this fish has them plus another, movement. Properly cared for they should ‘live long and prosper’.

The video gives information on care of the yellow tang. For those who want to see a photo of the fish click on the link.

http://commons.wikimedia.org/wiki/File:Zebrasoma_flavescens_Luc_Viatour.jpg

---

The Clown Trigger Fish

Though it is regularly seen in public aquariums, this fish is not commonly kept by aquarists. It is successfully kept by a good many nonetheless.

Seeing this fish in a local fish shop or anywhere else is an experience, the shape, the colours, it is really something. Anytime I see one anywhere I spend quite some time looking.

The fish is commonly known as the clown trigger and properly called Balistoides conspicilum. Why is it called ‘trigger’? This is because of the dorsal fin, for security the fish can go into a rock crevice and raise the dorsal fin, the second spine locks it in place. To release itself the fish exerts pressure on this second spine – the trigger – freeing the locking mechanism.

These fish are not suited to a reef aquarium as they could make a meal of mobile invertebrates and maybe some sessile invertebrates as well. As a snack, if the clown trigger can catch smaller fish it could eat them too. This would really please the aquarist! In addition, the fish could decide that the carefully placed reef rocks need re-arranging, again not an action that will endear it to the aquarist. Another reason is that the fish needs a lot of swimming space and in most reef systems the reef takes up a great deal of seawater volume.

So it is clear the fish is suited to the larger fish only system. Those with small and medium aquariums should not attempt to keep the fish as it could grow to 20 inches (circa 50.75cm). Many clown trigger fish being sold in stores are small, often only 3 or 4 inches, so growth must be allowed for.  An aquarium of 100 gallons (circa 400 litres) net or larger is the size needed. This is a large system as the fish requires rocks that form caves so that it can find security, these rocks of course reduce net seawater gallonage. The rocks should be firmly positioned so that they will resist any attempted design changes. On the same theme, heaters that are in the display aquarium should have guards fitted; these are generally available and not expensive. In a fish only aquarium a sump is a definite advantage as first it provides an area where heaters can be placed out of harm’s way and secondly it increases the net gallonage of the system. It should be remembered though that when stocking is considered the seawater in the sump is ignored.

Stocking the aquarium needs care. The clown trigger is very territorial and will take exception to another trigger in their area (the aquarium!) and could do the same with other large fish. Designed for dealing with crabs and other prey with shells, the teeth of the fish give the impression that it is not for messing with. So the fish should only be kept with other large or larger very robust ones that are well able to take care of themselves. These other fish should be of a different colour and shape.

Clearly if the aquarist wishes to keep a fish only aquarium with a high number of varied fish types, the clown trigger is not a fish to choose.

When introducing fish to the aquarium for the first time the clown trigger should be the last one in, this creates the chance for all the fish to ‘accept’ each other. It is also very helpful if, on introduction, the clown trigger is smaller than all other fish present. On no account should the aquarium be overstocked.

An aquarist could introduce the fish and find that it is impeccably behaved and wonder what on earth all the cautions were about. Another aquarist could find the fish a total berserker! So it’s best to be prepared.

Feeding is easy as the fish will take just about anything on offer, though for a fish such as this brine shrimp and flake are a bit of an insult! Pieces of de-frozen fish, mussel meat, shrimp and the like are foods usually taken without problem. The fish is confident and can be fed from the fingers, but beware of those teeth, an aquarist can be forgiven for being nervous! It has been reported that hard shelled food should be given on occasion as this wears the teeth. The fish becomes quite tame and if movement is detected near the aquarium it will usually beg for food.

Over time the fish will be seen nearly all of the daytime hours in open water and becomes a real pet and a favourite. They are very hardy and long lived if attention is given to maintaining a high quality environment.

The aquarist who can provide a suitable environment for the clown trigger is lucky indeed. 

The link is to some pictures and text:

http://www.aquaticcommunity.com/marinefish/clowntriggerfish.php

---

The Feather Duster Worm

Reef aquariums could be home to many life forms. One of these is the obvious, fish, in many aquariums these are small and inoffensive, and in bigger systems larger varieties could find a place. The major consideration with fish is that they are reef friendly.

Quite apart from fish there are many varieties of life. As the systems in this case are reefs the next is corals, both hard and soft. The corals are really what make the display a reef, the rocks may be ‘live’ and there may be fish flitting about, but it is the corals that make the picture.

Seen less are sponges as these are considered difficult by many aquarists and therefore they are not always attempted. It is reported that many sponges are not as difficult to keep as imagined, but their demise is often because of poor collection when damage is caused or when the sponge is allowed to come into contact with air. Algae can be another sponge enemy.

A spectacular life form that could be kept in a reef aquarium is a worm. Not just a worm though, this one is a real show off. The worm lives in a tube and is considered very attractive because of the head of feathery tentacles that appear. They are expanded into the seawater in order to trap food. The expanded tentacles do look similar to the old fashioned dust mop or feather duster that tackled cobwebs etc in days of old.

The worm is understandably commonly called the feather duster worm, or sometimes the peacock worm. The proper name for arguably the best is Sabellastarte magnifica. Feather dusters are common in warm seas and are usually easily obtained from local fish shops.

The tube extends from the rubble or rocks but all of it is not usually in sight. The tube could be up to 6 inches in length and the extended tentacle crown could be between 2 and 3 inches in diameter. The worm slowly extends the tentacles often stopping during the process and if everything seems fine the tentacles are completely extended. As they fully emerge they open up into the distinctive head.

The worm doesn’t appreciate strong seawater currents because of the head. If the current is too strong the worm could withdraw back into the tube. It is best to locate the tube in an area where only slight to moderate currents exist.

If a worm is seen to be hanging listlessly out of the tube it is likely to be dying.

When the tube with the worm within is first introduced to the aquarium the proper acclimatization technique should be applied. During this period it is best to ensure the tube is not exposed to air at all. Once the worm is ready for transfer the tube can be placed securely between rocks being careful not to crush it, when the worm is active it should adjust any faulty anchorage. Place the worm as said in an area of light to moderate currents, and lower down on the reef particularly if the lighting is powerful. The worm hasn’t any need for lighting as corals have. A worm that is positioned in bright light could be slow to appear until it is accustomed to it. It is reported that the worms do not like high temperatures – a top temperature of 76 deg F is sometimes quoted, though I kept one at 77 deg F for a long time.

Sometimes an aquarist can be alarmed as the worm drops its crown of tentacles. This could have been caused by stress produced by too high a temperature, excessive and sudden seawater currents, too large a change in seawater specific gravity or harassment. The first three are easily avoided. Harassment is avoided by ensuring that only suitable tank mates are present. Many common reef fish, such as damsels, dwarf angels etc could nibble at the worm’s tentacles. There are more that could cause a problem. Fish such as the copper-band butterfly (Chelmon rostratus) should be avoided. The best fish to keep with the tubeworm are small dottybacks, fairy baslets, gobies, blennies and the like. The worm can disappear into its tube at a terrific speed thus avoiding trouble, but repeated occurrences of this lead to stress. Once any problem has been corrected leave the worm alone. It could take a longish period to re-appear, and they are capable of re-growing a crown.

The tube worm feeds on very small plankton in the wild. In the aquarium once the worm has been given time to settle and is displaying its full crown of tentacles it can be target fed. Using a small syringe-like device, a small amount of fine filter-feeder food can be ejected ‘upstream’ and allowed to drift over the tentacles. If necessary seawater movement pumps can be temporarily turned off though this should not be necessary. It is best not to squirt the food straight at the tentacles or it is likely the worm will withdraw them believing danger is present. In an aquarium where there are many other filter feeders the food shouldn’t go to waste and the seawater quality shouldn’t be affected.

Looking at the suggested fish companions for the worm it seems the ideal home would be a nano aquarium. In these small systems it is usual to keep smaller inoffensive fish. The worm can successfully be kept in a large system subject to the other inhabitants, which means a lot of discipline could need to be applied by the aquarist.

The feather duster worm is a different and very interesting addition to a captive reef. Below is a short video.

---

Do We Feed Our Fish Too Much?

After feeding my fish the other day I settled back to watch them feed and then observe them as they returned to their normal habits on their ‘reef’ after all the food had gone.

This is something that I like to do as I find it relaxing plus it also gives me the opportunity to be able to check the fish are all healthy and active.

One thing I noticed was that even though they had just been fed they continued to scour the reef looking for food.

This got me thinking – do we need to feed our fish the amount that we do?

Is there enough food in an established aquarium to be able to sustain the health of any fish which are kept in an enclosed environment?

I am not saying by any means that anyone should stop feeding their fish – far from it.

What I was thinking about that evening is something that has stuck in my mind. In an established aquarium there are all sorts of life which are too small for us to see however fish are able to see them (and if they can catch them they may eat them).

With the amount of life which is in an established aquarium is there enough variety and quantity to be able to sustain the fish?

Would aquarists need to supplement this food to provide variety or for health related matters?

Would it be better for the fish as they would be able to feed lightly throughout the day rather than having one or two ‘mass’ feedings a day?

Another thing I was thinking about that evening was the feeding itself and whether the way we normally feed fish due to busy lives changes the in-built habits of fish. The majority of fish have an inbuilt urge to look for fish and then eat as much as fast as they can as they do not know when they will next find food. With the hand of the aquarist feeding the fish on a daily basis is this urge removed or reduced?

Perhaps this is all just me thinking too much but as said it is something that just stuck in my mind.

Maybe a test could be performed – not by me I hasten to add but by someone who both has more courage as well as the ability to scientifically prove the outcome of the test.

Until a test such as this is performed I am going to continue feeding the way I have been and recommend that you do as well.

If anyone has any answers or thought to any of the above questions then I would love to hear them.

---

Note – It has been a long time since I posted on Aquarists Online and it has been very nice to see emails asking if everything was ok etc. The reason I have not been posting for a while is that I have a lot going on at the moment and there do not appear to be enough hours in the day to get everything done. John has done a fantastic job in my opinion getting posts out as often as he does however although he is retired he is also an exceptionally busy man. I am pleased to say that I am now getting back into posting regularly on Aquarists Online – I hope no-one minds!

---

The Banggai Cardinal At Risk?

The Banggai Cardinal, properly called Pterapogon kauderni, is a fairly 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 and a long forked tail, again silver/black. It has become popular for obvious reasons.

A while ago it seemed likely that supplies of this fish from the wild would dry up because it appeared that the wild fish was under threat. Not a happy situation if correct.

The ‘under threat’ problem arose because it is believed that around 700,000 of these fish are collected for the aquarium trade each year. When the total estimated population in the wild is considered the cause for concern becomes obvious, this number is 2,000,000, so most would agree that the collection ratio is high. The fish only come from one small part of the Pacific Ocean so there is considerable collection concentration. The fish are mouth brooders (like freshwater cichlids) so perhaps the ratio of successful births to adulthood is high. However, whether that is the case or not, the fish only raise a few fish at a time so the ‘threat’ isn’t reduced. Open spawning fish produce huge amounts of eggs, and others such as clownfish produce far more fry. So the danger of insufficient natural replacement seemed real.

CITES became involved and the situation was under discussion. It very much looked as though a CITES ban on the importation of the fish would occur, if this ban appeared all imports into the US and EU would be prohibited.

Supply would be reduced to aquarists breeding the fish (a not impossible task) and commercial breeding which is being done, though limited.

However, as CITES ban did not occur. A considerable amount of discussion and agreed cooperation has avoided this. The government of the area has undertaken to strictly manage the situation, which includes training of local collectors and control of the numbers of fish collected relative to the estimated wild population. Aquarium trade groups and monitoring authorities have also undertaken to be involved. CITES had declared the fish as ‘at risk’ without further current action.

It seems likely that the number of these fish being exported from the collection area will or has reduced. This could have an effect on price, but who is going to complain in a circumstance such as this? Home bred fish but mainly commercially bred ones should counteract any fish scarcity to an extent.

Combined discussion and action seems to have produced a sensible outcome, the fish are being protected and at the same time interested parties such as aquarists and collectors have not been locked out.

The link shows a picture of the fish and some breeding information:

http://www.geocities.com/capecanaveral/hangar/6279/RaiseBanggaiCardinal.html

---

The Dwarf Lionfish

Lionfish are known to marine aquarists for two main reasons these being their predatory nature and their finnage which is unusual.

There are several lionfish types, probably the most well known one being the common lionfish, Pterois volitans, which is also the one usually most available. This fish can grow to around 12 inches.

The dwarf lionfish is named because of its comparative size, it could grow to around 7 inches. This fish can also usually be obtained without too much trouble. Though the adult size is around 7 inches, the fish is often for sale when much smaller. The link shows some photographs of the fish, some of these demonstrate how the colouration is reasonably effective as camouflage.

http://www.poppe-images.com/images/search_results.php?keyword_mh=Dendrochirus+brachypterus&x=58&y=9

Though there seem to always be occasional exceptions, the dwarf lionfish, proper name Dendrochirus brachypterus, is not for a reef aquarium. For a start it is a predator and will eat the smaller fish that are often kept, further it is likely to eat or damage some invertebrates.

In a fish only aquarium the dwarf lionfish should be kept with fish larger than itself because, as said, it will eat smaller ones and even ones more or less its own size – selecting the fish to go in a fish only community needs particular care because, again as said, the ones for sale are often small. Clearly they are going to grow and as they grow the fish population is going to reduce. Even at the initial small size they could eat other small fish. The predatory tendency maybe could be kept at bay or reduced if the fish is fed well, though this isn’t a guarantee.

Some aquarists keep the fish in a species aquarium as unlike tangs it does not require a large swimming space. This isn’t a bad idea as in addition to the community fish in the fish only aquarium being secure, the dwarf lionfish does not usually object to other same type fish being present. Obviously care has to be taken with stocking levels and also care with the fish themselves – one could maybe eat another if it was smaller.

A novice aquarist who wishes to gain some experience with a fish only aquarium could select the dwarf lionfish as a good addition, as the fish is hardy. The word ‘hardy’ does not mean that attention to seawater quality is not important, it is. The meaning is that the fish should withstand some common mistakes a novice could make, one prime example is overfeeding which will bring seawater quality down.

Mentioning the word feeding, this should be reasonably straightforward as the fish is predatory. It used to be said that small goldfish could be used as ‘feeder fish’ as they are inexpensive and last long enough in salt water to attract the attention of the lionfish. Nowadays this is not seen as ethical and is considered cruel. In addition, goldfish naturally live in freshwater, so is this food correct from a dietary point? The best way to feed the lionfish is to obtain frozen marine food such as lance fish, which is readily available. These are fairly small fish and the lionfish should be able to take them, if not they can easily be cut when frozen. Ensure of course that they are completely thawed (don’t thaw in a microwave as this reduces the nutritional value; thaw in some reverse osmosis water or seawater).

Feeding could present one problem and that is the food is of course dead, the lionfish is a predator and used to hunting live food so could ignore that provided. The answer to this is usually successful. Obtain some thin white cotton thread and fasten the food loosely to it. When the food is placed in the aquarium make sure it is in the vicinity of the fish and make it move about gently. Some patience could be required but eventually the hungry fish should take it. The cotton should come off easily. Peter once kept a lionfish in a species aquarium and it learned to take food in this way. In time, as soon as the food appeared at the surface it was taken without any delay. Having mentioned a potential problem with feeding it is possible that there could be no problem at all, it has been reported that the fish very occasionally will take anything meaty floating in the seawater, very small or not. Normal feeding of the lionfish is not required every day; every other day should be tried. The feeding frequency can be determined by observation, the fish should be reasonably eager.

The fish has spines that are venomous, just as much so as the larger lionfish. This needs to be remembered when hands are in the aquarium for maintenance. Also it is possible that a plastic bag could be punctured when the fish is being transported home, the dealer should ensure this is unlikely to cause problems by double or even triple bagging.

Once the dwarf lionfish is in the aquarium, having got there using the correct acclimatization technique, it should settle down quickly. The aquarist then has a fish that is unusual in finnage and different to observe. Though slow moving in comparison to others, it is a counter to the more usually kept fish. Perhaps the ideal is a species aquarium which sits underneath the larger display one?

---

The Copperband Butterfly

There are quite a few fish that could be said to fly the flag for the marine hobby. One of them is a member of the clownfish club, the so called common clownfish, Amphiprion ocellaris, with its gaudy ‘painted on’ colours.

The fish that for me anyway is the king (or queen) of the reef is the copperband butterfly, Chelmon rostratus. It is striking in shape and colour, drawing the eye like a magnet.

The fish has the typical butterfly shape, though its body seems a little more elongated vertically. The colours are vertically striped, alternating between silver and more narrow ‘copper’, hence the name. The snout is long, and the tail clear. The fish could grow to around 5″ (circa 12.75cm). A suggested minimum aquarium length is 3 ft (circa 91.5cm), though larger is better.

The fish isn’t normally bothered by another of the same species in the aquarium, though aquarium size could have an effect on this. In addition, the food that the fish requires could well be exhausted if there are too many predating the same sources. It is generally best to have one, and to try to ensure that there aren’t any others that will also predate on the copperband’s prey.

Following on from the last paragraph, the best aquarium for the fish is a very mature reef system. This is because there is likely to be a considerable population of tiny life that the fish will hunt. It searches carefully for food, slowly moving along the rocks and using its long snout to drag food out when found. The fish is reef safe and is unlikely to damage corals. However, fanworms and some other worms will be attacked.

The usual fish that could be found in a reef system are reasonable tank mates for the copperband. Fish that are overly territorial and/or aggressive should be avoided. The copperband defends itself in the usual butterfly fish way; it dips forward and expands the dorsal fin, confronting the aggressor with spikes.

The copperband appears to be ideal for the reef aquarium and it is. However, there is one major potential drawback and this is feeding. When a copperband is purchased the aquarist takes a gamble on whether the fish will feed or not. It is reasonably certain that the fish will follow its instincts and hunt for live food as previously mentioned. However, is there enough live food among the reef structure to sustain it? When a copperband is being considered for purchase a request should be made to see it feeding, hopefully it will feed. Take a note of what the food supplied is, this could be used until the fish accepts a changed diet – if it does. There are as many aquarists who report trouble feeding the fish as there are who have no trouble at all.

When I kept a copperband it fed, but what a performance it was! There was insufficient live food in the aquarium to sustain it, so additional feeding had to be done, unfortunately the fish refused any food in the water column. I had to obtain a small sheet of acrylic and fasten some rock to it (the rock was cut so it had one flat side). The rock was full of holes and crevices so these were filled with defrosted food, anything from brine shrimp to bloodworm. The rock was then lowered into the aquarium and leaned against a glass panel. Sure enough, eventually the fish came and looked at the rock but didn’t take anything. It was decided that this was because the food didn’t move (I have no idea if this was the real reason) so I gently shook the rock plate until the copperband came and took some. Unfortunately, the fish never learned that the food was there anyway whether the rock shook or not, it wouldn’t eat unless the rock was shaken! So the copperband received dinner when the others had eaten theirs.

There is an alleged benefit with the copperband that could please reef aquarists immensely, and this is that it attacks and eats Aiptasia anemones. These anemones are the weeds of the aquarium and a real nuisance, the aquarist has to keep them under control or they will spread throughout the aquarium. The copperband as said could assist in the battle and possibly even control the anemones on its own. However, (there’s always a ‘but’ isn’t there), although many aquarists report the fish does indeed have a go at the anemones, including some well respected ones, there seems to be just as many who advise that their fish ignored them. It may be that the fish attacks the anemones, damaging them and keeping them closed up. I don’t actually know, but any assistance in the battle with Aiptasia can only be good!

The experienced aquarist who has a decent sized well aged reef aquarium could obtain a copperband, bearing in mind the comments on feeding. Hopefully the fish will feed well and find lots to eat within the aquarium. Also hopefully it will take food provided by the aquarist. If all is well, the captive reef will be adorned by a fish that is – what can I say – superb.

---

« Previous Page — Next Page »