UV glass / shield for 400 watt MHs

[nos68]

I've had a pair of 400 watt MHs up and running and noticeing some bleaching on the corals. Was thinking of adding some UV glass to all of my reflectors anyhow, figure this won't solve the bleaching but may help and can't hurt.

My question is how thick do I need the glass? 400 watts is a lot and there's a ton of heat from these guys, even the e-ballast. I'd like to get them to be right below the edges of the reflectors.

Suggestions, ideas???

thanks,
Chris

[Casey]

I wouldnt do the glass maybe move the corals down some glass traps in heat I dont use glass in my reefs.

[nos68]

Yeah, I've already moved them down some, but the guy who I got the ballasts from recommended it (the glass sheilds) and I've lost one bulb due to water splashed from the tank (freak accident maybe). I want to say I've seen it done with custom boxes, maybe not.

Didn't think about the heat though...

thanks,
Chris

[Geoff]

i also do not have sheilds on my 400's. mine are 8" from the waters surface. how close are yours? explain freak accident. i have quite a bit of flow on the surface of my water and do not have splashing enough to cause buble breakage. now a fish splashing could i guess.

as for the coral, you may just need to cut your photoperiod down. then slowly bring it back up over several weeks.

G~

[wasabi]

ive got 4-400 watters 8-9inches over the water and about the same over many corals . no bleaching in 1.5 years