90g American Cichlid setup

SLB1976

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Thank you all for the suggestions and feedback. I will be just sticking with 1 Oscar in my 90g. As stated I’ve been with my always overstocked African cichlids for over 15 years, and always took pride in my fish tanks with proper maintenance. Hence why I believe over-filtration is never a bad thing.
 
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twentyleagues

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Thank you all for the suggestions and feedback. I will be just sticking with 1 Oscar in my 90g. As stated I’ve been with my always overstocked African cichlids for over 15 years, and always took pride in my fish tanks with proper maintenance. Hence why I believe over-filtration is never a bad thing.
Over filtration is not bad. But like I and others have said a 90 for a full grown oscar is like solitary confinement. If you go by rule of thumb (hate that saying) it 1.5× width and 3×length. So say an adult O is 15" you need a minimum width of 22.5" and 45" in length. When I stated a 120 I meant a standard 120 or a 4×2×2 tank not the 6' one, to narrow. Obviously a 180 would be perfect.
 
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FINWIN

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Its "funny" how this thread always seems to develop. It just keeps coming back over and over.
You will get one of two answers on this yes or no. And alot of reasons why. I personally believe that a 90 is to small in width for a full grown Oscar to be happy for life, but like I said and others have also with proper water changes and filtration you could do it. You can do alot of stuff but I wouldnt recommend some of it. You could live and survive in a 3×3×8 room but you wouldnt be happy. If we doubled the size youd be more happy. Until we became roommate's but may be happier then in the 3×3 still.
Can you keep sn Oscar a GT and some Acara? yes. Will you hate life with all the waterchanging? probably, will you have casualities? probably, will it be easier for your fish to get sick? possibly. I have also seen the oscar in a 55 and in a 75 and in a 90 they seemed fine......
I have also seen a solo oscar in a 120 and a 180 those were the best looking Os ive seen ever. A true wet pet happy to see people no hth no scars no tattered fins.
So the point is can it be done? Yes. Should it.......?
The "Oscars in a 55" stories rarely have a follow up. Wonder why.
 

SLB1976

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Not sure what Oscar 55 gallon story you're referring too, but I agree, but I am comfortable in putting a single Oscar in a 90g. Or a Green Terror with a few tank mates like Acaras.
 
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twentyleagues

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The problem with an Oscar in a 90 is that while probably big enough to be ok when full grown an Oscar can be up to 15+ inches. That gives him 3" of space when facing front to back. And again 3 body lengths of swim space. Well 2 because he occupies one of the 3. Ive seen healthy looking Oscars in a 90. So yes it can be done. Just like you could live in a 3'×3'×8' "enclosure" and be "healthy".
Monster fish deserve monster tanks not medium sized tanks. And I do believe oscars and othe CA/sa cichlids are trully monster fish. What they lack in shear size they make up for in attitude and personality. Imo they need space. Again can it be done yup. We keep people in the same type of spaces......oh but they get to go for walks!
Maybe this will help our Oscars in space constricted housing.
Take-your-fish-on-walks-with-this-backpack-aquarium-1-830x623.jpg
 
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Backfromthedead

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Im behind you on the 90 gallon. So long as your maintenance and care keeps up with the fishes needs it should be happy and healthy.

While of course i agree bigger is better, i think the 3'x3' analogy is a little extreme, maybe off base in comparison. I personally could not move at all in a 3'x3' room. I would liken a 90 gallon to something like a 40'x20' room.
 
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RD.

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I agree that bigger is always better, and even that a 90 will work, but IMO with this species, even more important than wiggle room, will be this:
I think once it becomes an adult ,50% water changes every other day would be needed in that small a tank, no matter how adequately the filter works, or the common malady HLLE, that oscars get when too confined, will be the result.
I also over-filter, always have, but with Oscars the issue is far more complex than simply keeping the water looking clean by maximizing filtration. Pristine water quality is paramount to keeping the fish healthy long term, which means keeping dissolved organic compounds low, bacteria count low, and keeping overall TDS and pH values stable.

Short term easy peasy while fish are small & growing. Long term, thousands of HITH stories on this forum over the years demonstrates just how susceptible this species is, even when in the hands of experienced fish keepers. The larger the fish becomes, and the smaller the space, the more challenging it becomes. It is at this stage that many hobbyists begin to realize that the larger tank, equates to more easily manageable maintenance regimes. Water changes & filter cleaning is a chore for most folks, and sometimes life can get in the way. IMO most cases of HITH are chronic conditions, that have developed over a number of months of not paying close attention to the little details. Just keep that in mind when moving forward with your O in a 90.

Good luck
 

FINWIN

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Probably because it ends in tragity.
Usually. Or they think it's ok because their "giant" oscar tops out at 8 inches. 😖

55 gallons are a "lazy" size for big cichlids because they're easy to get and pretty easy to transport and set up. They look bigger than they are when empty so people see a tiny O and think it will work. When that tiny O gets to 6 inches the panic sets in then they justify their choice by defending water changes. But to keep max water volume the tank is usually ugly, a wide open glass box inviting stress with no stimulation.

I think on Oscarfishlovers someone had a massive 14 inch O (2 yrs old, it was power fed) in a 90 gallon with a large piece of driftwood. I can tell you there wouldn't be space for anything but keyholes or dithers. The O was literally a centerpiece, floating in the middle. The brute was solo and didn't tolerate tankmates.
 
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twentyleagues

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Im behind you on the 90 gallon. So long as your maintenance and care keeps up with the fishes needs it should be happy and healthy.

While of course i agree bigger is better, i think the 3'x3' analogy is a little extreme, maybe off base in comparison. I personally could not move at all in a 3'x3' room. I would liken a 90 gallon to something like a 40'x20' room.
Yeah the 3×3 may be a little...off. 90 doesnt equate to 40×20 though, I lived quiet happily in an apartment about that size(little smaller). Lets say a 90 equates to a 16×8. But anyway it can live there so can you and like you and RD. RD. say its also or more importantly the pollution created by the Oscar.
Like I said ive seen Oscars in smaller tanks healthy. I had one in a smaller tank when I was young at about 10" I felt bad for him, and since I didnt have room for a larger tank he and my severum and common pleco (yup I said it) left my 125 to go live in a 200 something elsewhere. Mine was healthy, luckily even back then the one lfs I went to was a huge supporter of changing the water weekly. Most were on the once every 2 to oh i dont know say 6 months. He seemed happy also but even at 10" I could see he was "crowded" in the 18" wide tank.
 
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