Hi guys - was setting up a new aquarium the other day. I am still a beginner but know the basics. My tank was already cycled from some previous fish that have moved on. I just did a 50% water change and checked my parameters (all looking like mid/end cycle). I have a cold water tank but am sick of gold fish and the problems that they occur so I opted for some neat paradise fish. I put two of them into my 80L (20G) tank but thought that I could also fit in a couple more specimens as I was told the Paradise wouldn't get too much bigger and do not produce as much waste as goldfish. I asked the lady at the fish shop (who seemed very knowledgable about everything so far) what species she might recommend to go with the Paradise fish in a cold water aquarium. She recommended me some hillstream loaches. They seemed super neat so I bought two. I know I should have read up on them before purchasing but they looked so cool and I got excited I am ashamed to say. Anyways, since bringing them home I have since found out that their preferred habitat is of course the completely opposite of the Paradise fish. They like fast moving oxygenated water whereas the Paradise fish don't like much current. I was super annoyed about this because the fish shop told me they'd be great together - obviously not knowing what she was talking about. So I guess my question is - is they are any chance of them living together? To remedy for now I have direct my filter outlet (which comes down from an overhead filter unit at a right angle) across the back wall of the aquarium which is where the loaches have been hanging out. This means there is a strong stream across the back, but little disturbance in there rest of the aquarium. I have lots of nooks and ornmanets for them to hide in (I haven't seen them much since putting them in). For reference my water parameters seem fine I tested this morning and ammonia seems only slightly above 0, same with both nitrite at 0 and nitrate slightly above 0 - typical with introducing new fish? I will keep testing and do a water change every other day until they are settled. Is there any chance of them living together? If not, do you think I could return to the fish shop on the grounds that I was completely mid advised! I know I made a rookie mistake but I trusted the fish shop to advise me correctly.