14,000K MH burning corals - Aquarium Advice

IndyReefMan · 01-19-2006, 12:14 PM

For the past year, I have been running (2) 150w 20,000K [acronym:3e21899f45="Metal halide light"]MH[/acronym:3e21899f45] DE Coralvue on my 72 [acronym:3e21899f45="Gallon"]gal[/acronym:3e21899f45] bow reef. I supplement that with 130W 10,000K [acronym:3e21899f45="Power compact fluorescent"]PC[/acronym:3e21899f45] and 130W actinic and use them to create a dusk-to-dawn effect. The [acronym:3e21899f45="Metal halide light"]MH[/acronym:3e21899f45] photoperiod is 10hrs/day. I decided to switch to (2) 150W 14,000K [acronym:3e21899f45="Metal halide light"]MH[/acronym:3e21899f45] DE Phoenix to gain a little more PAR. I acclimated the 14,000K bulbs carefully with screens for a period of 4 weeks. Everything went fine. However, now that the screens have been removed, I can't keep the 14,000K phoenix bulbs on for any longer than about 3hrs/day without burning my corals. The [acronym:3e21899f45="Large polyped Scleractinian (stoney) coral"]LPS[/acronym:3e21899f45] corals are all near the bottom of the tank and I have various species of Acropora, Montipora, and Pocillopora near the top. The [acronym:3e21899f45="Metal halide light"]MH[/acronym:3e21899f45] bulbs are about 8 inches off of the water surface (that is as high as I can get them) which means that the closest corals are within about 15-16 inches from the lights (7 inches below the surface). The Montipora and a few of the Acropora suffer the most. When the lights are on for any longer than about 3-4 hrs/day, they start burning the tops facing the lights. What the heck is going on? How can 150W bulbs be burning Acro? Any suggestions? Am I doing something wrong? Any help or recommendations will be greatly appreciated.

TCTFish · 01-19-2006, 12:32 PM

I'm gonna give this my best shot and any one here who can add in...please do.

I'm taking a guess and say it may be due to the intensity of heat [acronym:2d7e725003="Metal halide light"]MH[/acronym:2d7e725003] put off. Maybe being 14,000K has something to do with it too. Even though acropora, montipora, table coral, etc. are momentarily exposed to air from low tides during the equinox, they are not getting super intense heat for any considerable length of time. The low tide lasts for what? A few hours at a time? So this would coincide with those lights being ok for only a few hours.

You may want to consider different lights to replace the halide, get a different halide, or get a bigger, deeper tank.

Are the coral on the bottom getting burned too?

Gatorfreak · 01-19-2006, 05:25 PM

What are you observing (physical symptoms) as the corals getting "burned"?

IndyReefMan · 01-19-2006, 09:54 PM

I keep my temp 80-81 degrees. The tank is in the basement and it's always cool down there so rising temps from the [acronym:54ff998778="Metal halide light"]MH[/acronym:54ff998778] are not an issue. The phsical symptoms are lack of polyp extension and whitening of the coral on the branches facing up so it's obviously a reaction to these bulbs. The bottoms of the branches (away from the lights) are just fine. The [acronym:54ff998778="Large polyped Scleractinian (stoney) coral"]LPS[/acronym:54ff998778] corals are not having much of a problem since I have them all so deep. Again, the [acronym:54ff998778="Small Polyped Stoney"]SPS[/acronym:54ff998778] corals are near the top and can't seem to handle the intensity of these bulbs for more than 3-4 hours/day. I could move them deeper but I don't want to do that because I won't have any corals near the top. I have since replaced the 14,000K Phoenix bulbs with the 20,000K CoralVue and everything is fine again. Too bad because those 14,000K bulbs looked awesome. I just can't understand how 150W [acronym:54ff998778="Metal halide light"]MH[/acronym:54ff998778] bulbs can burn the corals like that... most people seem to be running 250W bulbs on a tank of this size and don't seem to be having problems. Any other ideas?

ellisz · 01-19-2006, 11:37 PM

If acclimated properly seems like it could be a [acronym:f2005f8d37="Ultra Violet"]UV[/acronym:f2005f8d37] issue with the bulb. There were some bulbs last year that ended up having a problem with the [acronym:f2005f8d37="Ultra Violet"]UV[/acronym:f2005f8d37] filter on the bulb. This caused burnt corals.

Just an idea....

IndyReefMan · 01-20-2006, 08:49 AM

Quote:

If acclimated properly seems like it could be a [acronym:b0614e379d="Ultra Violet"]UV[/acronym:b0614e379d] issue with the bulb. There were some bulbs last year that ended up having a problem with the [acronym:b0614e379d="Ultra Violet"]UV[/acronym:b0614e379d] filter on the bulb. This caused burnt corals.

That's what I've suspected too. It does have a glass [acronym:b0614e379d="Ultra Violet"]UV[/acronym:b0614e379d] shield on it (it's an HQI bulb so it comes with a separate glass shield) but the ends remain uncovered. I talked to Jay at Premium Aquatics about that a few weeks ago and he suspects some [acronym:b0614e379d="Ultra Violet"]UV[/acronym:b0614e379d] could be leaking out of the uncovered ends. In order for that to happen, the [acronym:b0614e379d="Ultra Violet"]UV[/acronym:b0614e379d] radiation would be traveling horizantely to escape out of the [acronym:b0614e379d="Ultra Violet"]UV[/acronym:b0614e379d] shield and be getting reflected down into the display tank (assuming that [acronym:b0614e379d="Ultra Violet"]UV[/acronym:b0614e379d] light can be reflected like that). Any ideas how I could rig this unit to prevent the [acronym:b0614e379d="Ultra Violet"]UV[/acronym:b0614e379d] leaking out? It's a Coralife unit that clips on the back of the tank. I thought about placing a glass shield on the whole bottom to make it impossible for [acronym:b0614e379d="Ultra Violet"]UV[/acronym:b0614e379d] to leak out, but then the unit may not be able to cool properly.

TCTFish · 01-20-2006, 11:53 AM

Indy...you've hit the bullseye. That's exactly what my friend suspected when I asked him. He asked me if they were HQI and he said if so, then most likely it's the [acronym:f96f436680="Ultra Violet"]UV[/acronym:f96f436680]. These bulbs must be covered completely with a glass shield or they will damage the reef. These bulbs are made to be tucked in glass like that so if it's a well made, trustable company, then you shouldn't have to worry about cooling. What's more worth protecting? A few hundred dollar light or the thousands of dollars invested in your reef???

All you need to do is replace it with a different type of [acronym:f96f436680="Metal halide light"]MH[/acronym:f96f436680].

DragonForce · 01-20-2006, 04:12 PM

If the tips are getting white, the coral is growing not being burnt.

Phyl · 01-20-2006, 04:16 PM

If the entire exposed surface is going white then I'd agree it was being burnt/bleached. If it is just the very tips of the corals then pictures would be worth a thousand words. Some corals grow white at the tips as already suggested.

IndyReefMan · 01-22-2006, 08:07 AM

I went to a glass shop and had 1/4" plates cut to fit the fixture. I removed the diffuser and installed the glass so now the entire bottom of the fixture is covered in glass... no [acronym:c7c290fc8e="Ultra Violet"]UV[/acronym:c7c290fc8e] should be able to escape. The 14,000K bulbs are back-in and I'm acclimating so we'll see what happens. Also, which is a better [acronym:c7c290fc8e="Ultra Violet"]UV[/acronym:c7c290fc8e] shield-- glass or acrylic?

01-19-2006, 12:14 PM	#1
IndyReefMan Aquarium Advice Activist Join Date: Mar 2005 Location: Indianapolis, IN Posts: 187 Images: 10	14,000K MH burning corals For the past year, I have been running (2) 150w 20,000K [acronym:3e21899f45="Metal halide light"]MH[/acronym:3e21899f45] DE Coralvue on my 72 [acronym:3e21899f45="Gallon"]gal[/acronym:3e21899f45] bow reef. I supplement that with 130W 10,000K [acronym:3e21899f45="Power compact fluorescent"]PC[/acronym:3e21899f45] and 130W actinic and use them to create a dusk-to-dawn effect. The [acronym:3e21899f45="Metal halide light"]MH[/acronym:3e21899f45] photoperiod is 10hrs/day. I decided to switch to (2) 150W 14,000K [acronym:3e21899f45="Metal halide light"]MH[/acronym:3e21899f45] DE Phoenix to gain a little more PAR. I acclimated the 14,000K bulbs carefully with screens for a period of 4 weeks. Everything went fine. However, now that the screens have been removed, I can't keep the 14,000K phoenix bulbs on for any longer than about 3hrs/day without burning my corals. The [acronym:3e21899f45="Large polyped Scleractinian (stoney) coral"]LPS[/acronym:3e21899f45] corals are all near the bottom of the tank and I have various species of Acropora, Montipora, and Pocillopora near the top. The [acronym:3e21899f45="Metal halide light"]MH[/acronym:3e21899f45] bulbs are about 8 inches off of the water surface (that is as high as I can get them) which means that the closest corals are within about 15-16 inches from the lights (7 inches below the surface). The Montipora and a few of the Acropora suffer the most. When the lights are on for any longer than about 3-4 hrs/day, they start burning the tops facing the lights. What the heck is going on? How can 150W bulbs be burning Acro? Any suggestions? Am I doing something wrong? Any help or recommendations will be greatly appreciated.

01-19-2006, 12:32 PM	#2
TCTFish Aquarium Advice Addict Join Date: Jan 2005 Location: Southern California, USA Posts: 1,470 Images: 20	I'm gonna give this my best shot and any one here who can add in...please do. I'm taking a guess and say it may be due to the intensity of heat [acronym:2d7e725003="Metal halide light"]MH[/acronym:2d7e725003] put off. Maybe being 14,000K has something to do with it too. Even though acropora, montipora, table coral, etc. are momentarily exposed to air from low tides during the equinox, they are not getting super intense heat for any considerable length of time. The low tide lasts for what? A few hours at a time? So this would coincide with those lights being ok for only a few hours. You may want to consider different lights to replace the halide, get a different halide, or get a bigger, deeper tank. Are the coral on the bottom getting burned too? __________________ http://www.tricitytropicals.com ------------------------------------ We, as a people, know so much more about outer space than we do about our own oceans. This lack of knowledge can very well spell the dangers that lay in wait for us. The oceans surely would swallow us before a rock comes down to smite the planet of it's life. Nov/2004

01-19-2006, 11:37 PM	#5
ellisz Aquarium Advice Addict Moderator Emeritus Join Date: Sep 2003 Location: Indiana USA Posts: 2,676 Images: 9	If acclimated properly seems like it could be a [acronym:f2005f8d37="Ultra Violet"]UV[/acronym:f2005f8d37] issue with the bulb. There were some bulbs last year that ended up having a problem with the [acronym:f2005f8d37="Ultra Violet"]UV[/acronym:f2005f8d37] filter on the bulb. This caused burnt corals. Just an idea.... __________________ 180 gal Display, 100 gal basement sump, 33 gal refugium, 3x250 MH, 2x160 VHO actinics, zoos, some softies, LPS & lots of acros and other SPS. 100 gal prop tank plumbed into main system w/ 2x96 PC lights and 1x150 MH,

01-20-2006, 11:53 AM	#7
TCTFish Aquarium Advice Addict Join Date: Jan 2005 Location: Southern California, USA Posts: 1,470 Images: 20	Indy...you've hit the bullseye. That's exactly what my friend suspected when I asked him. He asked me if they were HQI and he said if so, then most likely it's the [acronym:f96f436680="Ultra Violet"]UV[/acronym:f96f436680]. These bulbs must be covered completely with a glass shield or they will damage the reef. These bulbs are made to be tucked in glass like that so if it's a well made, trustable company, then you shouldn't have to worry about cooling. What's more worth protecting? A few hundred dollar light or the thousands of dollars invested in your reef??? All you need to do is replace it with a different type of [acronym:f96f436680="Metal halide light"]MH[/acronym:f96f436680]. __________________ http://www.tricitytropicals.com ------------------------------------ We, as a people, know so much more about outer space than we do about our own oceans. This lack of knowledge can very well spell the dangers that lay in wait for us. The oceans surely would swallow us before a rock comes down to smite the planet of it's life. Nov/2004

01-20-2006, 04:12 PM	#8
DragonForce Aquarium Advice FINatic Join Date: Sep 2005 Location: Southern California Posts: 925 Images: 1	If the tips are getting white, the coral is growing not being burnt. __________________ 37 [acronym="Gallon"]gal[/acronym] all glass 50lb [acronym="Live rock"]LR[/acronym] 3' fine sand bed 1x Orange Stripe Prawn shrimp goby, 1x sixline wrassemated pair of true percula clowns, 1x CBS shrimp, 2x peppermint shrimp, 1x pistol shrimp, 1x tiger tale [acronym="Sea cucumber"]cuke[/acronym], ~20+ snails, ~10+ hermits, 1xserpent star. green Bubble coral, hammer coral (8 heads!) ,various Zoos,green finger leather, green star polpys ,[acronym="Mushroom coral"]shrooms[/acronym] 175w 10k [acronym="Metal halide light"]MH[/acronym] 28w actinic [acronym="Actinic lighting"]03[/acronym] 2x maxi jett 1200 Prizm skimmer (modded) Hagen powerfilter(for running carbon 24/7) nano arctica chiller

01-19-2006, 05:25 PM	#3
Gatorfreak Aquarium Advice FINatic Join Date: Aug 2004 Location: Gainesville, FL Posts: 617 Images: 2	What are you observing (physical symptoms) as the corals getting "burned"?

01-19-2006, 09:54 PM	#4
IndyReefMan Aquarium Advice Activist Join Date: Mar 2005 Location: Indianapolis, IN Posts: 187 Images: 10	I keep my temp 80-81 degrees. The tank is in the basement and it's always cool down there so rising temps from the [acronym:54ff998778="Metal halide light"]MH[/acronym:54ff998778] are not an issue. The phsical symptoms are lack of polyp extension and whitening of the coral on the branches facing up so it's obviously a reaction to these bulbs. The bottoms of the branches (away from the lights) are just fine. The [acronym:54ff998778="Large polyped Scleractinian (stoney) coral"]LPS[/acronym:54ff998778] corals are not having much of a problem since I have them all so deep. Again, the [acronym:54ff998778="Small Polyped Stoney"]SPS[/acronym:54ff998778] corals are near the top and can't seem to handle the intensity of these bulbs for more than 3-4 hours/day. I could move them deeper but I don't want to do that because I won't have any corals near the top. I have since replaced the 14,000K Phoenix bulbs with the 20,000K CoralVue and everything is fine again. Too bad because those 14,000K bulbs looked awesome. I just can't understand how 150W [acronym:54ff998778="Metal halide light"]MH[/acronym:54ff998778] bulbs can burn the corals like that... most people seem to be running 250W bulbs on a tank of this size and don't seem to be having problems. Any other ideas?

01-20-2006, 04:16 PM	#9
Phyl Aquarium Advice Addict Moderator Emeritus Join Date: Oct 2004 Location: NJ Posts: 2,107 Images: 30	If the entire exposed surface is going white then I'd agree it was being burnt/bleached. If it is just the very tips of the corals then pictures would be worth a thousand words. Some corals grow white at the tips as already suggested. __________________ Phyllis Join the NJ Reef Club Today! Saving the world's reefs one living room at a time! Next meeting: Eric Borneman, Dana Riddle, & Charles Mazel on October 25, 2008

01-22-2006, 08:07 AM	#10
IndyReefMan Aquarium Advice Activist Join Date: Mar 2005 Location: Indianapolis, IN Posts: 187 Images: 10	I went to a glass shop and had 1/4" plates cut to fit the fixture. I removed the diffuser and installed the glass so now the entire bottom of the fixture is covered in glass... no [acronym:c7c290fc8e="Ultra Violet"]UV[/acronym:c7c290fc8e] should be able to escape. The 14,000K bulbs are back-in and I'm acclimating so we'll see what happens. Also, which is a better [acronym:c7c290fc8e="Ultra Violet"]UV[/acronym:c7c290fc8e] shield-- glass or acrylic?

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Powerhead burning out?	lisajulia	General Hardware/Equipment Discussion	3	02-17-2006 12:53 AM
Burning Plants!?	fastfly48	Freshwater & Brackish - Planted Tanks	6	11-20-2005 10:04 AM
would I be burning my pump if...	gilraen	Saltwater Reef Aquaria	3	06-16-2005 03:55 PM
bleaching or burning of corals????	PiscesLou	Saltwater & Reef - Sick Fish or Coral	1	03-07-2005 08:07 PM
10,000K vs. 20,000K Halides	Electrobes	Saltwater & Reef - Archive	7	12-18-2003 02:23 PM