MH 911 call!!

[jlehigh]

I need some help on something..

Yesterday I came home to some baked corals, and I mean literally cooked. Turned several colonies dark brown as if I left bread in the oven too long. Come to find out the MH Bulb case had cracked, and I assume the excess UV baked the corals. None bleached or died, but baked... I can't describe it any other way...

I have a new bulb on the way however today I let a bulb run for 6 hrs. I turned it off and waited 30min to let the bulb cool down until it was cool to the touch. I then unscrewed the bulb and moved it to the reflector that had the previously broken bulb.

Not 2 min after I turned that light on I heard a ::crack:: !!! WTH! Sure enough the other bulb now has a crack in the same place the other broken bulb cracked!! What could have caused this!! The bulbs are 400W Coralvue Reeflux 10K's all being driven by a 400W PFO HQI ballast. These bulbs have been running perfectly for about 4 months. Could one of the other components cause a bulb to crack? Mogul socket? Ballast? Wiring?

I need to understand this before I inadvertantly break another 65.00 bulb!!

 

[Krish]

Man...I have no idea, but I'm really sorry to hear that. I hope you get it sorted out really soon...

 

[ScottT1980]

Any water hitting the bulbs? It would be a strange coincidence for it to occur simultaneously if it were due to water hitting the bulb, but certainly possible.

Take er easy
Scott T.

 

[reedman]

Maybe the reeflux bulbs aren't good for the HQI power?

 

[spongebob lover]

you know, kind of the same thing happened to me one time ( i had no corals though),
My lights were running fine and then all of a sudden i heard a huge crack sound (scared the heck out of me) and it turned out to be my ballast.
For some reason one side burned out, sorry if i can't tell you more because it happened about 2 years ago, but you should definetly check your ballast.

 

[jlehigh]

The severity has been downgraded... part of being an indecisive hobbyist is having spares for everything I swapped out both fixtures for the 400W DE 20K's I was running up until I switched to Mogul sockets.

I don't think it's a problem with the bulbs not being able to run on HQI ballasts since they have been running for several months now on a 9hr schedule.

Yesterday when the first bulb broke I was sure the bulb was splashed on because my sump was low causing the return pump to suck in air and the bubble popping probably caused the spray and bulb break, but then to see this other bulb suddenly break... That got me a bit panicked..

I'll let y'all know what happens when I test some new Mogul sockets bulbs..

 

[CarlaW]

Do let us know what happens, I am going to be putting a reefflux 10k on an hqi ballast this weekend.

 

[spongebob lover]

good luck dood

 

[jlehigh]

You will like them allot Charlie. I think I had a series of unfortunate events

 

[CarlaW]

You will like them allot Charlie. I think I had a series of unfortunate events

Yeah, all Kevin told me was to get my clippers out!!!

 

[liveforphysics]

The glass that surounds the quartz plasma holder is designed to sheild a degree of the UV produced from the bulb. The main purpose of the glass is to prevent rapid temp changes on the plasma holder which would of course shatter it. I have seen it charts with respect to the level of UV produced with and without the glass envelope, and the UV level was very low either way, however, this test was done with 5700k bulbs. The 10k bulbs you are useing are bound to be produceing a ton more UV, which may or may not have been the cause of the corals getting localy 'sterilized' so to speak.

If you are concerned about the potential of a balast current control issue, I could help you measure the current reaching the bulbs to see that its within the specification of the bulb manufacture.

The thing is though, I cant think of a potential malfunction that could cause MORE current to reach the bulbs without the addition of some capicitance... Caps often slowly or rapidly lose capicitance, but I dont see how its possible to gain it on accident.

Let me know if I can do anything to help you, I am still looking forward to seeing your beautiful tank one day in person.

-Luke

 

[jlehigh]

Nice post Luke! I think the evidence of higher UV output coming from higher Kelvin bulbs has been demonstrated in my tank. I'll post some pics when I get a chance showing the reaction in the corals. I consider myself lucky..

I agree the chance of a ballast malfunction causing the issue isn't likely. So far the 400W DE bulb running on the same ballast is doing fine.

You are welcome to come check the tank out though you may want to wait a month or so, because allot of cool changes are in the worx

 

[jlehigh]

Each noticeably impacted coral has lost at least half if not all flourecing pigments. Really wierd..

Here are some pics...

Efflo BEFORE

AFTER

Crispy...

 

[big t]

Charlie make sure you post pix w/ those bulbs, I am very interested to see how you like them since I am considering ordering 4 of them for myself.

 

[CarlaW]

The change will happen Saturday. There are enuf pics in my gallery for a before look, I'll post some Saturday afternnon when things get cooking!

 

[Skimmy]

it sounds to me more like it's your socket, mabye it's causing an arc somewhere? you said you were changing them out? you might want to check the ground in the socket as well

 

[Ed Hahn]

I was looking at stuff on PC and look what I found. I have no evidence of how accurate this is. http://www.aquarium-lighting-guide.com/metal-halide-ansi
I am thinking the socket as well or moisture.

 

[jlehigh]

I have two new bulbs and a replacement socket en-route.

So far none of the corals have shown any stressors. They are all still a gawd aweful rusty brown.. I hope the color recovers sooner than later.

 

[reedman]

One step forward and 3 steps back, eh John.

 

[jlehigh]

Shut-it! lol

The nice thing about having a big tank is when things go wrong in one section, you just gaze at one of the others & the center of my tank right now if plumb puuurrday