I will be transfering my cichlids convicts and one severum from a 55gal tank to a 75 gallon tank. I also plan on transfering the substrate, grey/white combined sand. I like this color sand because it seems to be a good compromise offering the advantages of a lighter sand with those of a darker sand. I am now considering painting the background. I guess ideally black or blue is recommended, but I picked up a paint that replicates a stone/slate finish (greyish). As I have a lot of varied colored rocks (some light;some dark), I thought this would be a good combination. What do you think?