I will be relocating my four 3" Clown Loach from a 37 gallon 'low tech' tank to a 65 Gallon 'low tech' tank. Yes, I know I'm going to hear that a 65 gallon is still too small for Clown Loach, but it's the largest tank I could get my wife to agree with. Anyway, so far I've been lucky; having no major issues keeping the Clown Loach with plants, except for Rubin Swords. So what I'm considering is using 2"-2 1/2" of Flourite regular for 65% of my substrate (for the planted area) and pool filter sand for the remaining 35%. I will be looking into ways to contain the sand, keeping it from mixing with the flourite gravel. Has anyone had any experience with using the two substrates in the same tank? I definitely want to maintain a natural look (no black or colored gravel or sand). I've been doing 25% water changes every 5 days with the smaller tank because of the bio load, but plan to cut back to every 10 days once I get the fish in the larger tank. I will be running two large filters a 110 AquaClear and a 2217 Eheim Filter. Do you need to be careful about sand particles getting into the filters, causing abrasion to the impellers? Typically I rinse the filter media on HOB filter every week (with tank water) and change the filter every other week. I only rinse the Canister media out every 4 months and replace every other time. I'm not too concerned about the canister filter because the impeller motor is after the stages of media, but the HOB filter has the opposite staging. Is there anything I should be concerned about?