Tiny Blue Tangs. Survival compared to larger ones?

[iamwhatiam52]

The stores here often have very small Blue Tangs (Paracanthurus hepatus).
They are an inch or smaller and are of course adorable.

How difficult are they to keep compared to starting with a larger one?

This one is to go in a 90 gallon reef with no large or aggressive fish, and will be the only tang.

 

[BangkokMatt]

They grow very rapidly. After 1 year I can't see them looking good / feeling good in anything less than a 220g.

They are easy to keep but...ime...need a large tank.

 

[JHemdal]

I cringe whenever I see those really tiny hepatus tangs offered for sale for two reasons: First, if they have not been fed properly as they move through the supply chain, they get too thin and then it is hard to get them back into good condition. Secondly, ask yourself WHY the baby hepatus are being collected - they didn't used to be seen, ever. Why now? Could it be due to over collecting? The same thing happened to Atlantic angels in the 1970's - we suddenly starting seeing 3/4" french angels, because collectors couldn't find enough of the 2" ones. Florida passed slot size limits for those fish, but nobody seems to be doing that for hepatus tangs.

I recently wrote an article for FAMA on this species, (June 09) but I see that it isn't available online. Maybe your local library has a copy? In any event, my advice would be to feed the tiny tangs 4x or more often per day, diced mysids, frozen cyclopeeze and crushed flakes.

Here is a link to an editorial I wrote that discusses (in part) the tank sizes for surgeonfish:

http://microcosmaqx.typepad.com/jay_hemdal/2009/01/beware-the-tang-police.html


Jay

 

[Amoore311]

Interesting article Jay.

In regards to that article, what tank size would you recommend for some of the following fish.

Acanthurus Leucosternon
Acanthurus achilles
Paracanthurus hepatus
Zebrasoma flavescens
Naso lituratus

Feel free to PM me the info if you would like. These are just some of the hotly debated fish right now in regards to tank size, and I would love to hear the opinion of someone with the qualifications you carry.

 

[JHemdal]

Amoore311,

I can't give you tank size for just a list of fish, it depends on their size at acquisition, the open swimming space of the tank and if you intend to hold them to their full captive adult size or not. Actually, I discussed part of the formula that I used in another thread a bit further down on this message board:

http://www.reefcentral.com/forums/showthread.php?s=&threadid=1685711

I'm sort of regretting have sent my Swimming Space article to Practical Fishkeeping, as it doesn't get much distribution outside Great Britain. I sent it to them because their editor is very critical, and I figure that an extra pair of eyes reviewing the material would help keep it as accurate as possible. However, now they own the copyright to it and nobody in North America has ready access to it.


Jay

 

[Amoore311]

Thanks for the response Jay.

I would love to read that article. Unfortunately I'm not sure I would have access to it on our side of the pond.

I was inquiring more or less about housing each fish for its lifetime in 1 aquarium, so the max size of the fish.

In regards to swimming space, could we use something like a very open rockscape, 1LB/Gallon L/R in the display holding the fish.... arranged in pillars.

Basically optimum conditions for the fish in question. As if we were going to design a system around each specific fish.


In regards to the Articles Copyright:

Would you be able to list your categories, and required minimum ratios here, or via PM? I would be able to analyze the ratio a bit more myself, instead of having to keep bugging you with questions on specific fish haha.

 

[JHemdal]

Amoore,

I'll have to check with the editor - RC has many international members, probably including people who work for Bauer Publications, and I'd hate to reprint something that causes any issues. Suffice it to say, for active reef fishes, if you take 80% of the listed adult size of a fish on fishbase.org, and then set up a ratio between that length and the length plus width of the open area of the aquarium, and if the ratio is better than 1:11, you should be in good shape to keep that fish in that tank for its normal life span. Sedentary fishes have ratios that go down to even 1:4 or so (think anglerfish). Things like lionfish and clowns might have a minimum ratio of around 1:6. I've run this through scenarios ranging from neon tetras to the whale sharks at the Atlanta aquarium, and have not found anything that doesn't fit. That said, some of the Europeans feel that it doesn't work for small danios - because it allows you to put a 2" danio in an eight gallon aquarium...however, as I point out in the article these are MINIMUM ratios - so if it worries you, just go with a larger ratio...


Jay

 

[Amoore311]

Great!

I'll start plugging some numbers and see how things turn out.


Thanks again.

 

[iamwhatiam52]

220 gal for a tang? I had thought a 4 foot tank would be enough, but that is why we ask questions here on reef central.
As for the posts in this thread about formulas, while I appreciate the advice, I'm not going to whip out my slide rule to see if the tank is big enough for a fish.
As others point out, many other factors need to be considered.

 

[iamwhatiam52]

As long as we have the attention of people with opinions on the subject, is there any particular tang that is better suited to a 4 foot tank?

 

[JHemdal]

iamwhatiam52,

You wrote - "I'm not going to whip out my slide rule to see if the tank is big enough for a fish" ...

Soooo, - instead you'll just reach and pull the tank size out of your ... err, take a wild guess at it then? Well, that's how its been done in the past, but of course, that's also how you end up with a suggestion of 220 gallons to hold a one year old hepatus tang (grin). FWIW: the sticky on the thread at the top here lists a minimum size tank of 100 gallons for a hepatus.

Figure the fish will reach perhaps 10" in captivity (12" wild maximum recorded size). No one year old hepatus is going to be anywhere NEAR that size, not if you start off with a 1" baby. There is absolutely no reason you could not keep a hepatus tang in a 90 for a year. If you keep it free from HLLE, you'll have no difficulty selling it back to your store at 6" or so and two or three years old. Figure 48" + 20" / 6" gives a ratio of 1:11, not a huge amount of space, but most certainly doable.


Jay

 

[JHemdal]

The mimic tangs Acanthurus pyroferus, tristis would be fine .... or a hepatus (grin).

J

 

[BangkokMatt]

<a href=showthread.php?s=&postid=15512419#post15512419 target=_blank>Originally posted</a> by JHemdal


You wrote - "I'm not going to whip out my slide rule to see if the tank is big enough for a fish" ...

Soooo, - instead you'll just reach and pull the tank size out of your ... err, take a wild guess at it then? Well, that's how its been done in the past, but of course, that's also how you end up with a suggestion of 220 gallons to hold a one year old hepatus tang (grin).

Erm....Not a wild guess at all Jay. I have a 16 month old hepatus in my 150g. It was bought very small and is now a beast. Too big for my tank (well, it certainly isn't visually appealing at least).
This is a first hand experience.So.... please don't assume that if something doesn't tie in with your formula it is simply guess work.

 

[victor90]

When I worked at a store the owner would order 50, around 45 would die

 

[iamwhatiam52]

Nnnooooooooo I won't just reach into my ----- and pull out a tank size. I'll reach into the experience of others on Reef Central, take them all with a grain of salt, and try to make an educated choice. I will heed your warning that a new home may need to be found for it in a few years. But NOT the fish store. That is murder. They will just sell it to a fool like me or worse. I'll give it to someone in the local club with a bigger tank.
Also, a lot depends on the temperament of the individual fish. I put a 2 inch Desjardini in my 180, and had to give it away in less than six months because it grew like a weed and raced around the tank like a whirling dervish driving my other fish nuts. This guy needed a 400. My yellow, also purchased at about 2 inches, after a year and a half is nearly 5 inches, but has a temperment more suited to the tank.

 

[massman]

<a href=showthread.php?s=&postid=15513682#post15513682 target=_blank>Originally posted</a> by ATB USA
When I worked at a store the owner would order 50, around 45 would die

What!!
That is shocking!
The owner is in the wrong game.

 

[victor90]

Only if you knew how many fish actually survive and die when they are shipped direct from the importer. It is not like this with all species though

 

[JHemdal]

BangkokMatt,

But your numbers with that ONE fish don't even back up your assertion - you have a year and a half old fish in a 150, and feel it isn't working. You then extrapolated that form the opinion that a one year old fish (starting at tiny size) would not be suitable for a 220. I disagree, and the sticky at the top of the page disagrees, and it doesn't come close to exceeding the formula that I worked out. I have two 15 year old 8 and 10" hepatus in 280 gallons of open water and they are fine, but that is still just two fish, so I would not present them as defense to any assertion I might make.

Why is your fish not visually appealing, is it out of proportion with the tank in your estimation? Is it deformed with HLLE or something? If it just exceeds your personal comfort level, then of course, that is your reality, and you should act to rectify it. However, you have to bear in mind that this does NOT mean that the fish's life span is being impinged - like it would be if the absolute minimun tank sizes were exceeded.

Your fish may well be "unhappy" in your 150, but that isn't a result of just tank size. It could be a combination of factors. Also, if your 150 has a big LR structure in it, then it isn't a 150. The calculations that I run use the volume of the open water space in the tank, I have a 1300 gallon reef that has only 400 gallons of open space, so I use that volume, not the gross volume of the tank...fish can't swim through rocks!

Jay

 

[JHemdal]

ATB USA, massman,

I would find a 40 day (post arrival at the retailer) 80% mortality rate on these tiny hepatus as totally within the realm of possibility. You see that all the time with tiny green chromis.

There is a group of fish that I term "grade B SE Asian" - basically, fish that are smaller than normal for the trade, coming out of Jakarta, Cebu or Manila. Often having a high percentage of "junk" fish that nobody wants; cleaner wrasse, tiny ocellaris clowns, green chromis, clown sweetlips, 1.5" bicolor angels, etc.

I think most folks in the trade have seen shipments like these. I've been working hard to avoid them since 1982, and for the most part I've been successful. Still, some stores use these sorts of fish as their primary stock!

In one study back in the 1980's, I found that 31% of a group of 450 Philippine fish died within 30 days of importation, and this did not include losses prior to their arrival in the United States.

More recently, (2006) I tracked a group of 100 "grade B" fish for 40 days after their importation. I can't locate the exact numbers right now, put the mortality rate for that time frame was over 40% - and no losses were attributable to common epizootics, Cryptocaryon, etc. Chalk it up to poor handling and cyanide.


Jay

 

[BangkokMatt]

Jay - Yes there is a lot of rock in my system and I didn't assume you were taking that into account.
I see your point. I think we had crossed wires. Apologies.

My fish WAS (feel free to read my thread) in good health. I was referring to the perceived crampdedness (I think that's a word) as I saw it. Not something I wanted for my tank.