That's a very good point. No where near my area of expertise but from what I've read Epoxy seems to be used as a coating on piping for potable water - however an EPA study on the subject does indicate that despite this - some level of leaching does occur from such coatings. Whether or not the leachate will show up in ICP testing we will find out - also if there seems to be any adverse affect on the inhabitants of the tank the nice thing is that as a single panel it will be very easy to remove. Will definitely share the outcome of any such experience. Forum experience seems to indicate it is a safe practice - and the hope is this will allow easier detritus removal as the tank is run. Will be cool to test the water side by side with the other tank to see if there is any variation that could be attributed to the epoxy sand bed.