FishProfiles.com Message Forums

I have three 3" or so RBP's in my 55 gallon at the moment but I am moving next week to my 75 gallon. I was wondering will that tank size be effcient enough to house 3 RBP's? I'm also planning on have lots of cories in there aswell, well the ones that are actually in with them now, so if I keep the P's well fed and provide a little cover should the cories and CAE be ok?

Hmm, could be risky.

Remember that in the wild, Piranha are assiduous piscivores that will demolish fishes larger than themselves! However, in the wild, they also cruise around their native waters in shoals numbering a quarter of a million individuals or so, which bestows upon them the ability to tackle far larger prey than they could alone.

One BIG problem that could arise is this - if one of your Piranha tries to snap up a Cory, the Cory's defensive mechanism - tough dorsal and pectoral fin spines - come into play, and the Cory could end up stuck in the Piranha's throat, resulting in the death of both fishes.

Even if you keep your Piranha well fed, you cannot reliably predict in advance what behaviour on the part of your other fishes will trigger a feeding response in the Piranha. It's a risk that I, personally, would not take.

Also, Red Bellied Piranha are capable of reaching 12 inches. Three active fishes that size would need more than a 75 - a 125 would be nearer the mark. You may find yourself having to move them up as they grow to larger quarters.


Panda Catfish fan and keeper/breeder since Christmas 2002

Yeah I am planning a 120 gallon for them down the road, but I will be away from home for a while so I just wanted them in a bigger tank then a 55 for the time being. I havn't had any trouble with them bothering the cories, but I do get what your saying. Sometimes when a cory goes to the surface the P's go crazy lol. Well I really wanted to keep some cories in there with them to cut down on the waste so my family would not have to clean the tank when I am gone. Any ideas on a bottom cleaner for them?

I dont think pirahnas and cories would mix well.... Pirahnas are usually kept in a species only tank. You are bound to loose a few cories if you keep this set up.

Inky

Any ideas for a bottom cleaner then?

Working on the basis that Piranha will be tempted by anything fast moving, one possibility for a fish that might (but I emphasise here only might) live alongside them is a Doradid catfish of some kind. Doradids are covered all over in spiny armour that makes the typical Doradid a virtually impossible mouthful for most other predators - I've described these fishes in the past as the M1 Abrams of the fish world, which isn't that much of an exaggeration!

Raphaels are probably a bit on the small side, but might possibly work, and have decent armour protection as you will find out if you try picking one up - it's basically a fish covered in its own razor wire!

There are bigger Doradids that would be well protected too, but here, the BIG question is the size of aquarium. One species that would possibly be safe as an adult upon account of being bigger than the Piranhas is Megalodoras irwini, but that is a two foot juggernaut of a fish when fully grown and would need something like 200 gallons all to itself! There's also the possibility that an adult Megalodoras irwini would be big enough to consider your Piranhas as lunch ... !!!

If you can find an armoured Doradid that reaches around 8 inches in length as an adult, then this is a possibility worth considering, though I emphasise that this would be a decidedly experimental pairing, and you would be taking a risk adding any other fish to a Piranha aquarium, even a chestnut burr with fins such as a Doradid ...

Mind you, Doradids live in the same waters as Piranha in the wild, so who knows? Plus, they're perfect candidates for bottom feeders in big Cichlid aquaria, because even the nastiest Cichlid soon learns that a Doradid is NOT a fish to be messed with ... apart from being covered all over in sharp spines and bony armour, Doradids also possess extremely powerful pectoral fins whose first rays are vicious-looking serrated spines (some species have triple rows of serrations on the pectoral spines) and these pectoral fins fold against a part of the body that is also armed with razor sharp defensive spines. If you get your fingers caught between the pectorals and that part of the body, the damage that the fish can inflict on your fingers is considerable, particularly in the case of a larger Doradid, and the fish defends itself from predators by trapping parts of the attacker in the manner just described. Most predators don't make the mistake of attacking a Doradid twice after that kind of encounter. However, I emphasise again that whatever goes in an aquarium with Piranha as other occupants faces the risk of attack, so if you ARE going to try this pairing experimentally, brace yourself for some less than delightful incidents just in case ...


Panda Catfish fan and keeper/breeder since Christmas 2002

I would be hesitant to put ANY bottom feeder in a pirahna tank. Anything that the pirahnas see living can easily become food. I still say that they are ment for a species only tank unless you have a really, really large tank (300+ gal) that is heavilly planted so that your fish can get away in an attack. I'm not trying to be mean, but I say no to putting ANY fish into that tank that is not a RBP.

Inky

Hahaha I dont take that as being mean, its good advice, thanks. I was just wondering b/c I wont beable to clean my take for 6 weeks at a time, so I wanted a good cleaning crew for it.

Even with bottom feeders (not cleaners) you will still need to vac the tank. I imagine 3 RBP's can be pretty messy, kind of like oscars are. You still won't be able to go 6 weeks w/out cleaning because the nitrates would be off the charts. You will have to find someone or some other way to clean the tank. Sorry.

Cories are bottom feeders, although they eat some extra food that settles on the bottom, they don't eat fish waste. They still need to be fed something like shrimp pellets. So, i hope you are feeding them something.

No fish eats waste (as in poo). So...sorry about your luck.

*Kristin*

I dont have to vac my 55 gallon now with the cories, I havn't yet and its been going now for 2 months. I know the cories dont fish waste, but its seems that the P's aren't all that dirty. They aren't messy at all really, there maybe a a little left over goldfish sometimes, but the cories eat that usually.

Its not good for cories to eat goldies

Pirahnas are all suprizingly messy and it is often hard to tell that they are (in the same sence that a pleco poos alot)

I still think you should move your cories. After awhile they may not be there to be your 'cleaning crew' Also, have you considered hiring someone to clean out your tank? (I know that is what one of my proffessors does) Your tank needs to be cleaned at LEAST every week with pirahnahs.


Inky

I also think you should move the cories. The pirahnas will eventually find them on the bottom and try to eat them. I see you have some in your 75g...could you move them there?

the Cory could end up stuck in the Piranha's throat, resulting in the death of both fishes.

That will eventually happen...when they find the cories.

Your tank needs to be cleaned at LEAST every week with pirahnahs

Agree with that. You may not see visible stuff...but you should be cleaning your tank atleast once a month...better if it was once a week.

And no, the cories shouldn't be eating goldies. Get some shrimp pellets for them.

*Kristin*

I feed them flake aswell, the P's eat the flake too. I feed the cories bloodworms, brineshrimp, and the sinking shrimp pellets. I just meant that I have seen the cories nipping at the body of a gold fish thats all. I might be able to get the tank cleaned every second week, thats about as often id say it would be possible. I plan to have good filtration aswell, I'm think a Aqua Clear 500 ( already on the tank ), and a aqua clear 300.