A basic dumb question..

[nanafish]

I know I am not the only aquarist out here with this thought on fish... When looking at an engaging fish at the store or online - by researching , it will list the size it can attain at maturity. Granted one should always take this into consideration before purchasing but I was wondering what the chances were that this would be the case in captivity?

 

[falconut]

I've had my Yellow Tang for 4+ years and he is no where near 8" - 9" as the websites list. He's more around 4" - 5" max. I believe that they list their maxium sizes, but they probably won't reach that size in our tanks unless they are in huge. But, I would use the website sizes as guide lines. Such as, I wouldn't purchase a fish with an adult size of 15" for a 90 gallon with the though that it shouldn't grow to the full size. Also, some fish are fast growers and some are slow growers, so that should also be researched. Hope this helps. This is just my opinion from my experience.

 

[mod0522]

+1. My scopas tang is 3 and he hasn't made it past 4". I wonder if the zebrasoma tangs are slow growers in general? On the other hand I bought an algae blenny at about 1.5" and he is now a whopping 5" in less than a year and a half, which is exactly where DD says he should be.

 

[BethanyM]

Its only a dumb question if you don't ask. =)

There are *some* fish that will not reach max wild size, but I would rather base my purchases on the max size than a guess. Some fish have maximum tank sizes more for their happiness/sanity than body size.

 

[crvz]

Really depends on a lot of factors, but I suspect most fish will get to about 80% of their max size in captivity. I wouldnt expect something less when making considerations about long-term stocking plans on a tank.

 

[tcmfish]

With lots of food, and lots of water changes (or a very large tank), your fish will get much bigger. I am still looking for a creditable source to back this up, but I know with many freshwater fish they release hormones in the water that inhibit growth. Also build up of waste could inhibit growth too, both of which are taken care of by water changes or in a big tank they are diluted, as the saying goes "dilution is the solution to pollution."

People have grown trout in tubes with freshwater being pumped in and then compared it to those with the same water and the ones with freshwater have almost burst the tubes. Also Koi breeders either to heavy water changes or grow fish in large ponds to get them to salable size quicker. I don't have a good source for marine fish, but I am still looking, but I would be willing to bet if you increased your water changes or put the fish in a larger tank that it would grow faster or larger than it has currently "maxed out" at.

 

[velvetelvis]

there are *some* fish that will not reach max wild size, but i would rather base my purchases on the max size than a guess. Some fish have maximum tank sizes more for their happiness/sanity than body size.

I wish more people thought like that, especially with very active fishes like tangs.

 

[nanafish]

I have a 180 that I am cycling. I love the way the panther groupers look. But if they attain their stated size of 116cm there is no way that I would consider this fish. But then I always wondered why fish stores stock these type of fish? Do they wait for the right dumb cluck to wander in and buy it?
I always like to try something different than the usual fish for a tank. So for that reason I look to the other fish that are in the wayside tanks.

***But then I am so damn happy about GPS's. Tell me which way to go and I will take a less traveled road. I'll get there- but I will have a good trip!

 

[Airwolf75]

Also remember a wild yellow tang, for example, can be live to be 40 years old. it will spend it's entire life growing. So a max size fish from the ocean is probably very old.

 

[velvetelvis]

But then I always wondered why fish stores stock these type of fish? Do they wait for the right dumb cluck to wander in and buy it?

Pretty much. If people buy fish like these, it creates consumer demand, and stores will meet that demand indefinitely as long as it makes them money. And unfortunately there are plenty of store owners who look at livestock and see nothing but dollar signs. Same thing happens with freshwater fish--look at how many stores sell inappropriate tank inhabitants like peacock bass, redtail catfish, and pacus, because they know some uninformed or indifferent bozo will buy them. Sure, the fish might end up dying because it's not properly cared for, or getting dumped in a local body of water somewhere when it gets too big (or when it loses its novelty and its owner gets bored and tired of taking care of it and looks for another way to impress his/her buddies), but irresponsible store owners don't care--they've made their profit and that's what matters, to them. :rolleye1:

Some people like to blame store owners for this phenomenon, but IMO the ultimate responsibility lies with us--with aquarists. If the demand isn't there for them, the inappropriate species won't be stocked--and it's no good whining that store owners don't warn customers first. That's what books and magazines are for. Caveat emptor.