Prevent this lighting problem form happening to you.

[andy4499]

Here is some advice about lighting. Inspect your bulbs on a regular basis.

About 2 months ago I purchased new 400 watt 12k MH bulbs on ebay for my tank and every seems to have been doing fine until about 4-5 days ago I noticed that one the right side of my tank it looked like all my corals had been burned by something. I started reading on line about this problem and many things could cause this problem. Some are alk or phosphates to high or an over dose on some chemical (calcium, alk, mag). So I checked all my levels and everything was fine, but the phosphates. They were high so I added something to lower that and things continued to get worse.

About an hour ago today I was thinking what could be causing this and check my canopy for something that could be wrong for about the 5 time and found that the glass part on my MH was cracked in half. I check this earlier in the week by glancing at it and it did not have this crack. When I pulled it out of the socket it was missing a 1/8” sliver that I guess is in my tank now. So I guess this part broke first earlier in the week and it did not crack in half right away.

Most of my corals will be ok, but the ones of the right side that were on rack high in the tank, big green slimmer and a large candy cane colony all took a big hit.

So the moral of this is always inspecting your bulbs even if they are new.