Not so much tank size but water quality in my experience. Hard to keep water clean with 2-9 inch oscars in a 55.
Can Oscars max out at 9"-10"?
- Thread starter Jonnyakawombell
- Start date
I agree; one little 4.5-inch Oscar was a pain to clean up after in a 55-gallon; I can't imagine cleaning up after two 9-inch Oscars.
My Big Boy was about 14 inches. He lived in a 125 most of his life. 
Yah 9 inches is either a stunt, a runt or juvie size. Brick was 15 inches and nearly 4lbs. Raised in a 225 with tankmates. Waste output was a LOT even though he didn't eat nearly as much past a foot.
Glad you rescued those Os. who knows, maybe they'll tack on another inch or two in time. Stunted fish often look old (bent, lumpy, tatty fins) so it does add to the confusion of "ageing" them.
Glad you rescued those Os. who knows, maybe they'll tack on another inch or two in time. Stunted fish often look old (bent, lumpy, tatty fins) so it does add to the confusion of "ageing" them.
I measured them before moving them from quarantine into my tank they were both inbetween 9"-10" then, probably closer to 10" to be fair, that was 6 maybe even almost 7 months ago now, and honestly I don't think they have grown at all, at the same time I also had another baby tiger Oscar in a 125g around 4", that fish was moved to my 420g around 3 months ago when it was 7"-8" , that same tiger has now overtaken the other two in length, not in thickness\girth yet however, but I'm confident these two not growing has nothing to do with my water conditions, like others have suggested I think it could be down to being stunted being in that small tank for a long time, or maybe down to genetics im honestly not sure, but one thing I know for sure they ain't growing lol.
Yeah, I'm honestly beginning to believe these 2 have been stunted unless I have 2 runts which seems unlikely, they don't look old or bent and there fins are perfect to be fair, wonder if they'll ever grow anymore or if it's permanent, time will tell I guess.
Although these two were in a 55g I honestly think water quality played a massive factor with my two's growth, the water was literally green as the tank was right in front of a window and the water stunk, she may not have been doing water changes for all I know, thinking back my biggest regret is not asking her now long she had them for.
Sounds like a perfect stunting scenario. There's no way 2 oscars in those conditions will be in ideal health and maximum potential size wise. ' Looking' healthy and being healthy are two diff things. A lot of 'healthy looking' oscars roll up from chronic nitrate poisoning over time. Main thing is they're in a much better situation now.
