my tin is similar to @PiscesPower and i too had no issues wtih sps, but tin can be present in many different forms so the triton test doesn't quite tell the whole story. 7 ug/l of tin in one tank could be in a much more toxic form than 10 ug/l in another, you just don't know.Some of the SPS losses could just be because it's a brand new tank. The lack of stability of a new system can have a negative effect on SPS. I have high tin on my last Triton (I got results yesterday). My SPS, are fine. Great polyp extension, good color, growing. My tin is 7.341 µg/l, I know that's in the, not quite red, level.