Heres some new loach video (10ft tank)

[chefkeith]

The clowns look good to me also.

The other thread with the video about the filtration answered most of my questions.

IMO, it sounds like the rocks are buffering the water just right. The dead live rocks will leach minimum amounts of calcium after awhile because nitrifying bacteria will grow on the surface and seal them somewhat. It's much like the concrete backgrounds that I see in many tanks these days. If water changes were large and infrequently, I'd be more concerned, but since this tank has a continuous water change system, the KH and GH will plateau and stay steady, and the pH will follow. Continuous water change systems are absolutely the best way to go for tanks like this.

I've used concrete cave structures in my tanks and monitored the TDS, KH, GH, and pH. Initially, it took about 1 month for the bacteria to seal the caves and for the water chemistry to stabilize.

I don't have any sharp rocks in my tanks, but some of my Clowns will scratch each other up with their razor sharp spines when they have hierarchy battles.