Well, on the clam, I think so long as it is situated under the middle of the bulbs on that side of the tank, it should be fine. I'm not sure about PC
, but reg floresceants and VHOS and HOs are the most intense in the middle of the bulb, I think PCs are more evenly distributed, but I still think it is prudent to keep it towards the middle of the bulb. FWIW
, I didn't see an algae problem
Hammer corals are not found in the sandbed in the wild and I would recommend you move it to the rock work. It would be very easy for the coral to pick up some sand, kicked up by a fish or crab, and irritate the flesh to the point of infection. I remember you were having an alk
, hammers are very sensitive to changes in alk
(mosly low alk
), so monitor these closely and take appropriate measure to keep them stable.