Not entirely true to me CD : The sand allows beneficial bacteria to grow that will "protect" the barbels. Even in a fry tank this is advisedIf you paint the outside bottom of the tank, it will work just fine for Corydoras. Bare bottom tanks only bother them because they are bottom fish, and from their perspective, they can't reach the visible bottom because of the clear glass blocking them. Paint it and they will be fine. I've kept and spawned a few species in bare bottom tanks, including albino C. aeneus, panda, and adolfoi. I've also spawned paleatus and aeneus over fine gravel, and saw no differences in behavior. For breeding purposes (and to me, there is no other purpose for keeping fish) bare tanks are preferable because fry are easier to see and feeding is easier to control.
Won't ve a matter of days, but it is a good idea.Hmmm interesting. I have some panda cories in QT in a bare bottom tank, with a rock background taped to the bottom as well as the back. They seem ok so far. Should I add a little sand for them?? They have been in QT for two weeks so far. I still need to switch my main tank to sand before I put then in.