Does Size Matter?

[gjscad]

I have heard from many people, LFS and co-workers alike, that a fish will grow to the size that the tank they are in permits. I think this is true of turtles but was wondering if the same applies to fish. Do they just tell you that at the fish store in hopes of making a sale? I had always had a large tank before so the size of the fish I had was never a problem.

I would love to know whether or not this is true. If anyone has had any experience with this I would sure like to hear from you.

gjscad

 

[loganj]

The fish will continue to grow regardless of tank size. I have seen Oscars in tanks that they could barely turn around in. Growth may be stunted due to improper nutrition and/or bad water conditions due to pollution in the too small tank.

 

[tkos]

What tends to happen is that fish secrete hormones in their waste. In a smaller tank these harmones can rise in levels quickly and if the water isn't changed very often it will stunt their growth. This is why goldfish in small bowls never grow up even though they could be over a foot in length.

There is always some growth stunting in our hobby due to the fact that we just can't all have 300 gallon tanks for bigger fish like balas and ID sharks. But still we should try our very best to give the fish what they need to grow and live long healthy lives.

A human child can easily be raised in a closet, though it won't make for a very good adult.

 

[Allivymar]

Of course size matters! Oh..erm...sorry, wrong subject

Seriously tho, except in specific case (like goldfish as tkos mentioned) most fish will continue to grow despite the size of the tank. When I got my plec, I hadn't done research first and did not know how big they got (up to 2 feet long). I had him in a 10g. When he put on 5 inches in 6 months I knew I had a problem LOL He now lives happily in a 55g and I may even have to go larger depending on his continued growth (his growth has slowed down immensely thank god). The tank size had NO bearing on his growth.

Is why its important to buy a tank which will accomodate the adult size of a fish. Keeps em happier and healthier in the long run.

 

[madasafish]

Yep, always hedge your bets, and go with the situation that is most humane. If you can get a smaller fish, do! There are plenty of smaller fish out there that are beautiful.

 

[Terry]

This might be a load of tosh what i am about to say but i think that the fish can sence the amount of water that they are swimming in and also how crowded it is, this will tell the fish how much he can grow and at what rate of growth.

 

[tkos]

Yes, that is a load of tosh. Some fish just keep growing, other secrete hormones that stunt their growth. No real sensing things going on. Either way in too small of a tank you end up with fish that don't get to live their true lifespan.

 

[Allivymar]

I don't agree either Terry. Again, using my plec as an example, he put on 5 inches on 6 months in a 8g hex tank (leaving him just over 6 inches long in a tank that was 6 inches on each side...just slap me ok? LOL I didn't know at the time how stupid that was). He is now in a 55g tank, is just over 8 inches and has maybe put on 1/2 inch since moving in there (he was in a 25g in the interim, where he added a little over an inch). It seems the BIGGER the tank he's in, the slower he grows LOL

My angelfish was in that 8g hex tank along with the plec; he too grew to adult size in about 6 months in there, making him 3 1/2 inches long from nose to the root of his tail fin (and that doesn't include the 5 inches of veiltail!).

I believe, unless there are fish which give off growth suppressant hormones in the tank, the fish will continue to grow if well fed and kept in good water conditions. Just won't be very happy or healthy.

 

[Terry]

tkos & allivymar
Thankyou for telling me i am talking a load of tosh,hahahah i am not disagreeing with anybody it was just a line of thought.
I know that fish use there lateral line to detect vibrations in the water, that warns them of other fishes and obstacles nearby and some fishes have developed sophisicated aids to help the cope with darkness and murky water. And that some fish use electrical magnectic fields. so they were the sort of lines i was thinking.

 

[webmoose]

This is one of the most popular questions I get from friends... Even a friend of mine that has plec in his 10G disagreed with me.... I am only going by what I have read but it does make sense that certain fish need a certain amount of space. The other thing I was told one time was that if you get a big enough filter you can add more fish than the rule. My response was watch your fish and see if they are happy in the tank. :?

Kinda on this topic any idea how you measure fish.. I know I can look up and see that the fish will get to a certain size and I can tell that if I have x fish at x size potential I am within a range and you should always stock to a certain range or below that.

BUT if I just want to know how big my one fish is...... I know it isn't really important but I would like to be able to know that my bronze cory is 1.5 inches long and he is still growing.. etc.