If there's no other tankmates moderate filtration should be fine. I used 2 AC70's for my small dats in a 55. Worked fine. I went with barebottom but sand is another gd option. Maybe a few tall fake plants for decor should work out gd. I would avoid decor that could possible blind your dats. They chase & bump their eyes which is common with dats. Limit hiding spots. The more they see you, the more they will feel comfortable to eat. gd luck