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Does tank size affect growth rate?

Feb 11, 2008
Hi Everyone,
My baby O. bimaculoides (now over 3 months old) have not grown as much as I expected (according to Forsythe and Hanlon 1988 O. bimaculoides hatchlings raised at 23C double their weight every 15 days). The babies are eating very well (they take 10 or so live mysids daily, and there are always more live shrimp available to them, so I assume they are feeding to satiation, and I give them the occasional hermit crab if I can find one small enough) but I am not seeing anything like the growth rate reported in the aforementioned paper. One thing occurred to me just now; is there any evidence that Octopuses "grow to the size of the tank" as is the conventional wisdom I have often heard bandied around for fish? The reason I ask is that I have been keeping the babies in small individual containers within my water-conditioning tank to avoid escapers (the plan being of course to put them in ever bigger containers as they grow), but now I am concerned I may inadvertently be retarding their growth.
Does anyone have any thoughts on this subject?
Many thanks,
Fish sizes affected

hi, Lene
yes i am pretty sure that the sizze of a tank can affect a fishes growth rate, but i dont think you should worry about it retarding the growth rate forever, only while it is in the small tank. i have a V.small 9 litre tank inside and i had an algae eater about 4cm long and very thin for about 2 years but then he started attaking my other fish so i moved him into the fish pond outside wich is a lot bigger 40 litres or more at least.
I was cleaning it out and took the water level down and by pure chance i managed to find him. And OMG he was HUGE:shock::bugout: he was like 10cm long and hilariously wider too.
So i am quite sure that the size of a tank deinitely effect the size of a fish. And plus my cousin has a pond the size of a swimming pool and put a shubumpkin in it and OMG was it big ! like the size of half a cricket babt and very fat!.

so yes the tank affects the fish.

Bye Lene hope it helped . x
3 things,

1) This thread is 4 months old.
2) NO, tank size ABSOLUTELY DOES NOT effect animal size when it comes to salt water. The smaller size of your octopuses may be attributed to underfeeding, or they could just be taking a while, who knows, as long as they're healthy.
3) Welcome emma!! Why don't you introduce yourself!