i agree u deffinetly need sand or bare bottom. me and 3 of my friends bought retics and 2 of us have sand and 2 have gravel. both of my buddies with gravel lost there rays in a week and me and my other buddy have had ours over 2-3 mos now. i have a very black sand which i like alot cause it hides alot of the poop. they say u should do water changes all the time with rays but i guess ive been lucky. i do one water change per week and average 40-80 ppm of nitrates. good luck with urs bro