I switched back to my old MHs (2x 175W) over the weekend. About seven months ago, I replaced the MHs with 2x Hydra 52 HDs. However, since then I lost around 60 gbtas out of 80+ clones. My tank looks horrible. At first I thought it might be due to water quality but parameters looked good and stable. The tank has been up and running since 2006. The 80+ gbta clones started from one gbta. The biggest change was the lights. I acclimated the tank and while at the time looked like the anemones seemed ok with it, over time they started to shrink, disappear, or move. None of them bleached though. I had tried different settings and intensities. Bought a par meter and had 350 par at WL and around 100-125 par at the sand bed. Unfortunately I didnt have par readings from the MHs prior. Anyways, after switchung back, I found that the MHs put out a par of 225 at WL. The remaining anemones seem to be doing better since the switch. I do like the Hydras and may switch back once the anemones amd tank get back to normal but setting the intensity appropriately. Thought I would share my experience so far.
