Hiker, I have extra crushed coral substrate should I add to the bottom of sump with cheato? Does yours flow go from right to left in your pic? What size pump and over flow do you have on your 29 gal? I also have a 29 gal that I need to add a sump to. Do you have a thread of that tank set up I could look at? Thanks for the help I will be putting this together this weekend If I can find the time.