Are my Metal Halides burning my SPS??

[Mako Shark II]

Folks – I’ve been racking my brain, my friends and the LFS’s for answers, so now I’m throwing this one out to the Sharks:

Am I cooking my SPS???

Generally speaking: My tank is in fabulous condition. My softies are (Really) exploding. My fish are growing and healthy, but my SPS (Green Bali slimer, Millipora, any Acro’s, Birds Nest, Monti Caps, etc.) are bleaching out.

My water params are good:
550 Calc
9 Alk
8.2 pH
0-Trace Nitrites & Nitrates
Frequent water changes "on the Fly" by the way… Pressurized waterchanges via a Closed Loop waste line
Temp. 78

Dry Goods: (all <6-month old bulbs)
120 Gallon full Reef tank (filled w/ aged, stable & established rock) Balance of groceries below.
2 each 250 watt XM single-ended Metal Halides (12� above water surface) 20,000K Color Temperature, on Coralvue electronic ballasts
2 each 54 Watt Giesemann T5’s: (1) Actinic + and (1) Powerchrome in Ice-Cap reflectors (14� above water surface)
2 each Coralife 1 watt L.E.D. Moonlights (3� above water surface)

Light Cycles:
LED’s come on: 2-4:30 PM, then 10:45 - Midnight
Actinics come on: 4-6, then 8:30-11 PM
MH’s come on: 5-10:30
(Full Dawn to Dusk simulation)



The SPS are typically in the upper third to middle of the tank’s depth, but over time, anything new, slowly bleaches out or eventually dies, while my sacro’s, mushrooms, frogs, hammers, GBTA, RBTA, Duncans, GSP, paly’s and everything else(!), looks great!

So I don’t get it. Am I cooking them? I can’t keep them alive and everything on paper, appears great.

This is kickin' my tail!!!

[jph]

if your LPS are happy, you're not going to be cooking your SPS. something else is going on. LPS are more sensitive to (too much) light than SPS.

any close up pics of the bleaching SPS?


ps: your Ca is rather high. are you dosing anything to keep it there?
what are your Mg levels?


J.

[schigara]

So the Mh is running just 5.5 hours per day?

[Toddrtrex]

Like " jph " asked, what are you Mag levels, and for that matter, what is your phosphates.

I have similar lights over my 58, and not having any issues -- and mine are a lot closer. So, I think there is another issue, could be flow, some water parameter level, or too much nutrients.

[recife111]

My water params are good: 550 Calc

550 cal is not good, should be about 400-450ppm.

[deeznuts]

Originally posted by recife111
550 cal is not good, should be about 400-450ppm.

I doubt thats whats bleaching them.
My Cal is about 600 and my sps are fine.

[Mako Shark II]

Originally posted by recife111
550 cal is not good, should be about 400-450ppm.

Yes, thanks recife111, but I agree with deeznuts.

I'm using Oceanic salt (SG 1.025 - 1.026) and its high in Calc out of the bucket.

Toddrtrex: Is it possible I'm OVER feeding them??? Hmmm....maybe. They get a pretty healthy dose of DT's, or reef planton + Cyclopeze + Reef-Nutrition (whatever their Omega 3 goo is.)

[Mako Shark II]

Originally posted by Toddrtrex
Like " jph " asked, what are you Mag levels, and for that matter, what is your phosphates.........some water parameter level......

Mag & Phosphates.... Good point. I'll check & advise. Thanks All!

[Toddrtrex]

Originally posted by Mako Shark II

Toddrtrex: Is it possible I'm OVER feeding them??? Hmmm....maybe. They get a pretty healthy dose of DT's, or reef planton + Cyclopeze + Reef-Nutrition (whatever their Omega 3 goo is.)

That COULD be causing some water issues, but not sure. I have never fed any of my SPS, and they are all doing great.

[Mako Shark II]

Really, I'm feeding the Water and smaller inverts, not the SPS, who should be getting food via zooxanthella from the lights.

[stanlalee]

sure its not too little light? 20k XMs 12" above the water really isn't strong lighting. thats weaker than a good 14k 175w set up. with softies and LPS exploding that would be more likely than too much light BUT I too think its most likely something in the water chemistry that might not be normally tested or isn't obvious on the surface.