Major SPS Loss...Do you use a shield under your SE bulb?

[benf]

Basically, last Wed. i believe, my center 400w MH bulb exploded an appx. 3" section out of the side of it. The bulb continued to work. It wasnt til Sat morning when i was about to do some maintenance did i notice a piece of glass laying on my screen covering my tank. Only lights on at the moment were my actinics. I look up and notice it came from the center MH bulb.

At first , back on Wed. I thought i may be having an issue with Alk cause i was seeing some STN and RTN going on, yet the numbers were reasonable and continued to test for a couple days. By now it was saturday and thats when i noticed the culprit. Anyhow, i have now loss 9 SPS colonies from the center of my tank. Of course these had to be my prized pieces of the tank.

The reason i put this thread in this section is to see if anyone puts tempered glass under the SE MH bulbs. I know it will cut down on PAR, but look at the alternative. I think its poor bulb design that it should continue to work with a crack and ~3" section of the bulb missing. Had it quit immediately i would not have experienced this loss. Also, had i not had the screen over the tank, the glass would most likely gone in the tank and who knows when i would have discovered the break. :mad: :(

[ReefBum]

I have a shield and it gives me piece of mind for the potential scenario you described.

[benf]

Thanks for the input...did u notice much loss in brightness or coral response?

[ReefBum]

I've been using them since I started my new tank 10 months ago so I can't provide any insight on that. You will lose par but I think it is easier to keep a lense clean than a reflector. You will also lose par with a dirty lense.

I recently switched from 400W bulbs to 250W bulbs and I really like the results. I made the switch because some of my corals got burned since the light was too intense. Now the 250s under the lenses are working great.

[benf]

ok, thanks for ur info... forgot to ask...is the glass u are using regular or tempered(uv)?

[slojmn]

I have never used an extra piece fo glass to shield my SE bulbs. In my old tank I had a bulb crack and break apart, luckily it sort of hung there and some of the UV light was still shielded by the outer sheath of glass. needless to say a bunch of corals got burned pretty bad below the bulb but all recovered. I found the broken bulb the same day it broke so the corals were exposed to the UV light for, at the most, 5 hours and probably less. Sorry to hear of your losses.

[benf]

<a href=showthread.php?s=&postid=11827487#post11827487 target=_blank>Originally posted</a> by slojmn
Sorry to hear of your losses.

thanks...you got lucky u found it in such a short period of time.

[ReefBum]

<a href=showthread.php?s=&postid=11827226#post11827226 target=_blank>Originally posted</a> by benf
ok, thanks for ur info... forgot to ask...is the glass u are using regular or tempered(uv)?

Regular glass.

[benf]

thanks!

[phurst]

<a href=showthread.php?s=&postid=11826833#post11826833 target=_blank>Originally posted</a> by benf

I think its poor bulb design that it should continue to work with a crack and ~3" section of the bulb missing. :(


Unfortunately all SE bulbs are that way. The outer envelope is simply a UV shield and has no effect whatsoever on weather the bulb works or not.

[Rickyrooz1]

benf, what bulb melted? The Aquaconnect 14K?

[benf]

no, will pm u which one

[benf]

Well, just got home and it appears i will have lost 13 SPS corals..both Acros and Montis.

[Rickyrooz1]

Did you replace the bulb yet?

[benf]

yeah, i have my AquaConnects that were on the tank before with only 4 months on them. So i put one of them in place of the bad bulb. I am going to get some prices to cut glass for the housing. I prefer to get it cut in a T or I. about 5" across in the middle to shield the bulb from splash with enough openning on both sides to help keep it cool.

[Rickyrooz1]

Even when you switched back to the old bulbs the corals are still losing tissue?

[benf]

yes, the damage was already done by the UV radiation

[Rickyrooz1]

Sorry for your loses. What corals were they? Any Limited Editions?

[benf]

no...but one of them was a want among local refers..many expressed interest in frags...it was a very nice baby blue acro.

[Emster]

Ben, still sorry to hear about your loss. For what its worth I use a plexi glass shield in my fixture that I believe is UV plexi (it came from hamilton) and you have seen my growth. Don't worry about the shield effecting the par, if you ask me its easier to clean the shield then it is to clean the fixture.

[Kinetic]

sorry to hear about the problem =( I heard that if the bulbs get wet that will also contribute to possible cracking. I'd say if you can spare a bit of PAR, get a UV shield.

I know there's currently a DE lamp that is also UV shielded now too, but going into any fixture/pendant that isn't custom, you'll get double UV shield, but it might be safer.

[slojmn]

When I had my experience I ran my lights for 1/2 the time on the tank as I figured the corals were burned pretty bad and they couldn't take a lot of light until they healed up. Try cutting back on your light period for a week or two.