14 August 2016
Edit add: I had to re-level the tank this week. Noticed that the cardboard sheet it sits on was crushed nearly flat across the front, there was a definite angle from the back. At topline I couldn't see any variation, but if it was visible to the eye at base, that was enough to bother me. I got out the level and verified that. I figure the weight of the furniture it's sitting on must have slowly compressed the carpet, and now it is tilting forwards. When the tank was half-empty during water change, I carefully lifted the front edge of the furniture up with my knee- just enough to slide another shim under each corner, and check with the level again. When I had them in the right position, I used a serrated knife to score the cedar shims flush against the furniture legs (they're short and fat) and break off the excess. It still bugs me to see the angle in the cardboard, but I can't change that out unless I empty the whole tank.