Determining Fate of Bully Red Tail


(((****found new home for the shark!****)))

I just recently got pulled into the cyclonic vortex nature of fish keeping!!!! Went from 0-55 very quickly and now need advice.

this is a long tale, so feel free to jump to the bottom for my QUESTION.

I work at PetSmart and purchased a 55 gallon kit because the price was sooooo amazing. I already had 5 gallon and a 2.5 gallon each with a single betta. The goal was to wait til fall to set up the 55 then someone brought in an amazing!!! red tail shark. Um. Because it was aggressive. I guess I thought his personality would change because I thought he was beautiful.

We put the bettas back together with a divider in the 2.5, put him in the 5 and got the 55 up and going.

Then someone brought back a Blood Red Parrot because it was getting picked on. So I brought him home, divided the 5 gallon and he and the shark shared that tank. Basically I was a slum lord for a few weeks. Continued to monitor the 55 for water parameters/cycling so I could get everyone out of the cramped quarters. I was testing water in the little tanks and doing partial water changes every other day.

55 became ready enough, moved both ‘rescue’ fish together into the 55 and had MMA smack down immediately.

So now, the shark is back in the 5.
The male betta has the whole 2.5 to himself.
The blood red parrot, the female betta, and 4 dwarf gouramis (added yesterday) are doing fine together in the 55.

QUESTION-is it remotely OK for the shark, as the ONLY fish, to stay in the 5? By the basic ‘1 inch of fish per gallon’ rule it’s not too far off. But for the fish type, bigger is better, 55 recommended so he can swim and live his best life. My concern is that I am already stop #2 for him for being aggressive. Can he live with other fish. How do I re-home him knowing he’s so aggressive

secondary concern-the male betta, as a single fish, should have the 5 gallon which was the plan for when the 55 was up

We are willing to get ‘one more tank’ (says every hobbyist, over and over again), either a 10 or 20, but don’t see the practicality of having multiple tanks each with only one fish.

1. Shark in the 5?
2. If not, advise for re-homing :(
3. If not re-homing, could he live in a 10?

Thank you for reading and please be nice. I know this is a mess of my own making and I just want to have more minds/experiences to help m figure out next steps.

pictures of the original 4. No pics of the gouramis.


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Sounds like a bit of a predicament. But no, the shark cant stay in the 5 or a 10 - they get too big and are too active for either.

They can be really aggressive (yours sounds even more so) so you may be better rehoming unfortunately.
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Hi Ekunk64. Hope you’re keeping well.

A red tail shark shouldn’t be kept in a 5 gallon or 10 gallon. They’re both too small for an active fish that grows upwards of six inches. Not to mention the bioload of such big fish is too high for small tanks like this to comprehend. A high bioload means more production of ammonia, which, in a cycled tank, will become nitrate (nitrogen oxide isotope containing one nitrogen atom and three oxygen atoms (NO3)). When nitrate creeps above 40mg/L (or 40ppm) it will become a concern to the fish’s health. As you mentioned learning about cycling and testing, I’m sure you know well about managing water quality and what I’m talking about already. In short, it would be hard to keep the water quality stable in a small tank with a red tail shark.

Ammonia (NH3) —> nitrite (NO2) —> nitrate (NO3).

Red tail sharks are very territorial and making them work with other fish is a balancing act even in big tanks like the 55 gallon. This is why (personally) I don’t like them. They’re branded as “sharks” to distract people from the facts and make sales, as people end up thinking they’re real sharks. I’m almost certain this fish used to belong to an owner who bought it because they were captivated by the idea of owning a shark, only to be forced into rehoming it to you.

The inch per gallon rule should be destroyed IMO. People believe it and end up in your exact situation. I wouldn’t keep a single 50 inch fish in a 50 gallon as the fish would be longer than the tank!

Sorry to hear things have turned out this way for you. :( I won’t criticise your for any of this as this is a messy situation that requires patience to pull through.
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If the one inch fish is a neon tetra then the inch/gallon kinda works. If you consider how many neon tetras you can fit in the body volume of a redtail shark, then you will probably get closer to the real number.

Everything needs to be said has been said, but I think they are very pretty without thinking them as sharks. A large aquarium well planted with broad leaf plants would work, but if others can't get out of his sight, there will be constant aggression. I did keep three of them together in a 20g when they were less than 2.5" but that wouldn't work with full grown ones.
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Tonight at work I helped someone with a 400 gallon tank and a 65 gallon tank and he will take the shark!!!! He doesn’t have one and is pretty sure that one of the two tanks will work for him! Will take him next week. Thanks for your comments!
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You’re welcome. I know rehoming such fish creates a bad feeling, but it also saves you the ordeal of trying to keep them.
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