hey guys, i have been having the worst time trying to keep my kh up as well as calcium, im starting to think that maybe the sand (a bit larger than what i would consider sand) is the problem since I purchased the 20 gallon off of craigslist. I also have algae problems once in a while even though i dont have any fish that I feed. I was thinking of replacing the sand with an even larger substrate to cover the bottom so while im at it, i might as well do some plexi/ rods to clean up my rockwork and make it solid. I'm not really sure what type of fiberglass rods you are recommending from home depot, also i'm not sure what type of glue you use. You really just drill a hole for the rod, insert it and glue? what is the width of the plexiglass? Thanks for the help guys, sorry im a newbie!!