So after my 10 gallon basically crashed last week (thanks everyone for the help), my cories were moved into my 29 gallon. My pleco is leaving me this week, leaving room open. Currently there are 4 cories in my 29 gallon. Are they fine with just the 4 of them? BTW I've noticed since the move, my bronze cories have gotten a lot of their color back (this is a good thing right?) They are dark now, compared to the pale color they were in my 10 gallon. Anyways. my 10 gallon now has jus the 4 platys, and the 6 neons. Bottom is getting messy and Id like a bottom feeder to take care of it. Which would be a good choice for a 10 gallon with that stock, and a sand bottom. It has 1 live plant in it. Thanks for your help in advance.