View Full Version : MH UV Radiation

10/11/2011, 06:06 PM
Perhaps I am being too cautious, but I figure it can't hurt. I have a 400 watt MH setup lying around the the 4x40 watt T12 won't be enough for my 24" deep 55 gallon for some corals and clams...thinking of future.

I bought a 20,000K Plusrite mogul base (single ended) and put it into the reflector. The consensus seems to be that any single ended MH bulb is totally safe since it has the outer bulb. This is true for UVB and UVC but not all of UVA (60-70% gets through). I will be setting up my desk next to this tank so I want to be absolutely sure it is safe.

I put a 24"x24" square sheet of 1/4" glass across the two shoplights under the MH to add another layer of glass. I also put up tin foil to shield any part where the bulb could throw light without going through the second pane of glass (other than a space at top on one side for intake for fan, and the far end which will be at a part of the room with shelves and nothing else). So anywhere I sit will be behing the outer envelope of the bulb plus the 1/4" plate glass.

Is this too much? Still not safe to sit by the tank for hours?


10/11/2011, 06:16 PM
Should I bother with the 4x40 watt 6500k bulbs? I don't think just a 400 watt 20,000k will be enough for the health of the fish, etc. Will it?

10/11/2011, 08:09 PM
You should be fine. I used 2 400 W in my living room without any UV problems, I'm from S florida though so I'm used to high UV from the sun. Just be careful with your eyes. If you are worried about stray UV light leaking through get something that floresces or glows in the dark and place it where you would normally sit. Also if you don't have any corals or clams yet you don't relly need the MH the fish could care less. 6500 is very yellow though but it's up to your tastes.