Hello everyone, my 2 motoro stingrays, 1 hystrix stingray, and myself are new members here. As of now they live in a 38 gallon tank, its an odd size being 36"L, 12"W, 20"D. All my rays eat like pigs, are very active, and appear very happy. The motoro rays are both about 5" across the disk and the hystrix is 3". I know they need more room now even though they appear happy. They could get as big as 2 feet across so I need to step up big. I've even considered a baby pool. The problem I have right now is this. I'm running 3 filters on this tank now. A whisper 4 and 2 whisper 2 filters. They keep the tank very clean and give plenty of surface agitation, BUT everyday when I wake up and when I get home from work the impellers have stopped because they are clogged with grains of marine sand. I've tried using filter material and sponges on the intake to catch the sand but this slows the waterflow to a trickle. I'm going to get a real big tank when I can afford it so I need a real big filter as well. I want to get the filter first and start using it now. What is good for a 100 to 150 gallon freshwater tank, that wont clog with sand when these guys stir it up as stingrays love to do? I've got alot more questions where this came from but I'll get to them later If all you out there can help me. yet very