Catfish

[UncleWillie]

While, yes, madtoms are great for smaller tanks since many never get over 5'', I'm afraid ChunkyLover will not be able to get these imported into the UK. While some North American fish have been introduced there, I doubt any of them are suitable for a 35L tank.

I wonder if something like a few corys would interest you. I may be wrong, but I think there are some cories that do just fine in unheated tanks (remember, unheated tanks is not the same thing as cold water tanks). The only problem is that they need to be in groups. I fear you may be in a pickle and you choice of bottom feeders is quite limited in a tank that size... Sorry

[MChambers]

I wonder if something like a few corys would interest you. I may be wrong, but I think there are some cories that do just fine in unheated tanks (remember, unheated tanks is not the same thing as cold water tanks). The only problem is that they need to be in groups. I fear you may be in a pickle and you choice of bottom feeders is quite limited in a tank that size... Sorry

Agreed. Corydoras paleatus, which is quite common, supposedly does well down to 59F. (You didn't define coldwater, so I'm just guessing.) You might do some research in the Cat-e-og at www.planetcatfish.com. It looks like there are about 10 catfish that have a similar temperature range.

[chunky lover]

Well i found a catfish not sure on type,he grows to about 5 cm and has settled in great already had a name picked for him,missus called him felix as in felix the cat.

[Aeonflame]

Those should be in a school of at least 5 and do not belong in a 35 liter tank

[Goes to 11!]

+ 1 to Aeon, You are not going to see anything approaching their natural behavior when kept solo.

What temp is this tank?

[gm72]

+2. That will be a very unhappy fish kept solo.

[Aeonflame]

Also, while it may be controversial... ime, cories are very active fish that need more floor space than a ten gallon tank can offer