OKay, I have a question. I have a little 10 gallon tank with a few swordtails in it. Unfortunately my gravel color is just kinda ugly in this room. I have had the fish in the tank for a little over a month, and I think it is nicely established. What would be a safe way to change the gravel? I should have thought of this earlier, but I got the gravel of free, and thought I’d like it at the time.