Lighting for a 30" deep tank

bwade209 · 01/09/2010, 08:56 PM

Just wondering if my 2X175W ARO ballasts with 175w Iwaki single end 10000K bulbs would be sufficient...Also have a 2X250 Odyssea fixture with Phoenix double ended 14000Ks and 4 PC's... or am I going to have to sweet-talk the wife into yet ANOTHER light upgrade? (PC's to T5's....T5's to better T5's....T5's to MH/PC's....MH/PC's to MH/VHO...) I think her patience is running thin....LOL

The tank is going to be a mixed reef, mostly LPS/softies but I'd like to have some SPS in the mid-upper level of the tank. I don't have enough liverock to build very high sturctures upwards yet without the rest of the tank looking empty. Upgrading from a massively overcrowded 72g bowfront to a 300g...

Hal · 01/09/2010, 09:08 PM

175W MH's for a 30" deep tank sounds a little underpowered. I don't know anything about the Oddysea fixture or PC lighting, so i can't say if they would provide enough additional par. I would think that sps even mid level would be a little underlit.

Having said that, you don't say what kind of reflectors you're using, and a good reflector can make a huge difference.

I run 250 MH on my 30" deep tank and like them very much.

luv4paws2 · 01/09/2010, 09:49 PM

I have 150's on a 31" deep tank with sps at the middle/top and they do just fine.

bwade209 · 01/09/2010, 10:06 PM

I was incorrect on my bulbs....they are 175 w Iwasaki 15K not 10K... the reflectors are Sunlight Supply Reef Optix with electronic ARO ballasts

I was under the impression the reflectors give the light from the bulb a better spread throughout the tank rather than a deeper penetration??

Mini_GBR · 01/12/2010, 12:05 PM

They do help to give a nice spread, but really what they do is help to capture the half of the light that is pointed towards the top of the hood by reflecting the light back down into the tank. If you had no reflector, you would lose a great deal of the light that hits the hood, thus almost losing half of you light output (a 250w bulb essentially becomes a 125w bulb). With a high polish reflector you regain almost all of the backside of the bulb. A good example of this are those really big telescopes that have HUGE, highly polished mirrors (a reflector) in order to capture as much light as possible from the cosmos in order to reflect it back into the eye piece. Hope this helps.

pbnj · 01/12/2010, 02:59 PM

Keep in mind, there's a difference between "surviving" and "thriving". I can't see using anything less than 250Ws on a 30+ deep tank, unless it was mostly softies.

nanojg · 01/12/2010, 04:10 PM

those iwasaki's have more par than a lot of 250 watt bulbs, I think you will be fine with sps on middle to top.

01/09/2010, 08:56 PM	#1
bwade209 Registered Member Join Date: Oct 2009 Posts: 513	Lighting for a 30" deep tank Just wondering if my 2X175W ARO ballasts with 175w Iwaki single end 10000K bulbs would be sufficient...Also have a 2X250 Odyssea fixture with Phoenix double ended 14000Ks and 4 PC's... or am I going to have to sweet-talk the wife into yet ANOTHER light upgrade? (PC's to T5's....T5's to better T5's....T5's to MH/PC's....MH/PC's to MH/VHO...) I think her patience is running thin....LOL The tank is going to be a mixed reef, mostly LPS/softies but I'd like to have some SPS in the mid-upper level of the tank. I don't have enough liverock to build very high sturctures upwards yet without the rest of the tank looking empty. Upgrading from a massively overcrowded 72g bowfront to a 300g...

01/09/2010, 09:08 PM	#2
Hal Registered Member Join Date: Oct 2001 Location: Longmont, CO Posts: 1,889	175W MH's for a 30" deep tank sounds a little underpowered. I don't know anything about the Oddysea fixture or PC lighting, so i can't say if they would provide enough additional par. I would think that sps even mid level would be a little underlit. Having said that, you don't say what kind of reflectors you're using, and a good reflector can make a huge difference. I run 250 MH on my 30" deep tank and like them very much. __________________ Some days it's not even worth chewing through the restraints. Current Tank Info: 250g starphire: 72x28x30, BeanAnimal drain with an oversized non-durso emergency drain, 4 inch DSB, 3x Reefbreeders Value LED fixtures, SWC/MSX 300A skimmer, Geo kalk reactor, 3 Vortechs w/bb, carbon reactor, and a RKL

01/12/2010, 12:05 PM	#5
Mini_GBR Registered Member Join Date: Mar 2006 Location: Los Angeles Posts: 62	They do help to give a nice spread, but really what they do is help to capture the half of the light that is pointed towards the top of the hood by reflecting the light back down into the tank. If you had no reflector, you would lose a great deal of the light that hits the hood, thus almost losing half of you light output (a 250w bulb essentially becomes a 125w bulb). With a high polish reflector you regain almost all of the backside of the bulb. A good example of this are those really big telescopes that have HUGE, highly polished mirrors (a reflector) in order to capture as much light as possible from the cosmos in order to reflect it back into the eye piece. Hope this helps. __________________ RC does not allow URLs in sigs for anyone but site sponsors. Current Tank Info: A 30,000 gallon aquaponic farm. But looking to get back into the reefing hobby with a 60g anemone only tank

01/09/2010, 09:49 PM	#3
luv4paws2 Registered Member Join Date: Mar 2008 Location: Lakeland, FL Posts: 612	I have 150's on a 31" deep tank with sps at the middle/top and they do just fine.

01/09/2010, 10:06 PM	#4
bwade209 Registered Member Join Date: Oct 2009 Posts: 513	I was incorrect on my bulbs....they are 175 w Iwasaki 15K not 10K... the reflectors are Sunlight Supply Reef Optix with electronic ARO ballasts I was under the impression the reflectors give the light from the bulb a better spread throughout the tank rather than a deeper penetration??

01/12/2010, 02:59 PM	#6
pbnj Registered Member Join Date: Apr 2009 Location: Austin, TX Posts: 381	Keep in mind, there's a difference between "surviving" and "thriving". I can't see using anything less than 250Ws on a 30+ deep tank, unless it was mostly softies.

01/12/2010, 04:10 PM	#7
nanojg Registered Member Join Date: Jan 2009 Location: Lubbock, Texas Posts: 2,174	those iwasaki's have more par than a lot of 250 watt bulbs, I think you will be fine with sps on middle to top.