Abalios do need a bigger tank. right now I have 12 ranging from 4-6in in a 180g and it looks crowed. will be going my 240g when I get it set up. I personally like light colored sand for these fish. I will take some pictures of the sand I got, which JK47 recomended, which is awesome. I use to have black sand and it made them look darker. Their vertical black lines, like the ones in the picture, would show all the time! so I switched to a lighter sand and now they are their natural golden color.