I'd like to change my substrate to sand. Currently I have a medium sized typical aquarium gravel. Can anyone tell me the best process and if it is easier to clean. I find all the food gets under the gravel and no matter how much I vaccuum I still seem to have stuff in there after the cory's stir it up. Can I just remove lets say, half the gravel and replace it with sand or should I do it in smaller increments? I have read that many of you use pool filter sand so that is what I am going to look at today. Does it settle quickly. Does it vaccuum well? I use the syphon type vaccuum and run it into a bucket. I have no idea what to expect.