PlanetCatfish.com

What are good tank mates for a bumble bee catfish? I want to set up a 125 gallon tank.

what species are you interested in getting as you have the smaller south american bumbles like microglanis sp.around 60-80mm to the bigger bumbles such as batrochoglanis at 200mm+ and pseudopimelodus around 245mm+ with a mouth almost as wide as they are long!

I have been keeping 3 microlangis iheringis housed with several otocinclus and neon tetras in densely planted tank with driftwoods. Since iheringis are generally non-aggressive (though they may prey on fry), I think most community fish (given similar water temp. and ph)should be fine.

It is a giant bumble bee catfish. I dont know if they are sutiable for tankmates. If not how big of a tank should I buy?

If you're talking about Cephalosilurus: they can only be accompanied by large tankmates, so imo you will need more than 125 gallons.
If you refrain from tankmates, however, I think you could do with less, because they're known to be rather lazy, if you know what I mean.

It is a P. Bunofius (incorrect spelling)

It's too bad you just now pop up with a name, because it turns out that my previous reply is good for nothing.
Furthermore, if you know the spelling is incorrect, what's wrong with checking the correct spelling first and putting that in your post?
This isn't McDonalds. You may do things yourself here

there is a good description and examples of tank mates in the cat-e-log under pseudopimelodus bufonius

Be very careful with p. bufonius. They are highly predatory and though more limited by gape than, say cephalosilurus, they can match their aggression.

I tried to keep a 5 inch specimen with eight 6 inch silver dollars only to find two savaged overnight.

I've heard many similar stories.

Batrochoglanis are predatory but peaceful with fish too large to consume. Better still - why not try microglanis?

Good luck,

Nick