Compatibles?

[Ken Sauer]

I have 2 corydoras paleatus and 2 serpae tetras. We are looking to add two more to the 10 gallon tank. We don't want aggressive fish and we don't want lower to the bottom fish. Any suggestions as to which fish might get along well with the four we already have? Thanks

 

[Treestone]

I'm going to make the assumption that your water chemistry matches the requirements for those species. A 10 gallon tank is very vague, could you please specify the dimensions of your tank. Generally speaking for an average ten gallon those fish you're keeping in there at the moment will grow too large and are too active. Both species require schools of at least six to maintain condition. These conditions may be fine in the short term but you will not see the full extent of their behaviours and they will be very likely to be stressed out to some extent which is no way to keep fish. I would move them into a larger tank and bump up the schools, or you could sell them or return them to your lfs.
A far more ideal stocking would consist of a single species tank. For this, there are many options it would help if you could specify what behaviour you want to see out of your fish. It would also help if you could give us some water chemistry values?

 

[Ken Sauer]

GH between 30 and 60. KH 40. PH 7.0. NO2: 0. N03: 0. Water temp: 77 degrees
It is a normal 10 gallon tank.
So you are saying 2 of each is not good and 10 gallon is not good?

 

[Treestone]

Your water is very soft, which suits your stocking at the moment yet it is more difficult conditions in terms of upkeep. Sorry, but a 'normal 10 gallon tank' doesn't help me much lol. I should've clarified but the measurements or at least the model will help.

Yeah, two of each of those species is less than ideal as they habit massive schools in the wild, in groups of more than six, ideally ten in most cases, you can start to provide the conditions for this behaviour and they will therefore feel more comfortable and outgoing. Serpae tetras are notorious fin nippers and will show aggression in small groups such as described, to help disperse and ease this aggression a larger school and a larger tank must be implemented. Peppered cories grow quite large, are very active and require schools.

Just curious do you use rainwater, RO or tap water?