Newbie Needs Help w/ MH Setup

tx_kyle · 04/29/2006, 10:20 AM

I bought an existing 120G (4x2x2) setup. The setup came with a 11" (inside measurement) deep canopy with two 400W Radium 20k bulbs mounted in a full length reflector. Unfortunately, one side of the dual ballast is kaput. I also don't know the age of the Radium bulbs.

I've had 40G reef lite with 130W of PC lighting up and running for 17 months. Frogspawn, ricordia, sun coral.. easy stuff. I bought the new setup with the hope of hosting clams, BTA, and eventually maybe even SPS.

As I see it, my options are

1) Buy a new dual ballast and keep the Radium 20k bulbs.
2) Scrape the entire setup and buy something new.

Some random thoughts...

1) Given the tank is only 24" deep, 400W may be overkill. Seems like 250W would be fine and would cut down on heat generation.

2) Many people think 20k is too blue. I haven't seen enough examples to make my own judgement but, as a general rule, I'm sort of an "average" kind of guy. Also you have the consideration that some livestock (clams?) actually need a certain "color" of light.

3) My canopy is only 11" (inside measurement) deep. It seems that would preclude mounting a lower temperature MH fixture, say 10k, and then supplementing with VHO actinics or something similar.

4) I don't mind spending some money to do things right. I just can't afford to spend a bunch of money experimenting.

Any advice would be appreciated. Thanks!

fishtk75 · 04/29/2006, 12:34 PM

I just upgraded to a 120 tank and had two 250's 10k on a 75.
You are right about heat the 250's MH I have put out heat so if the one's you have the 400 will have more heat may have to buy a chiller.
I had to put two Icecap fans on top to move the heat out and a third fan blowing over the sump to get more heat out plus it in the basement this was on the 75 looking at 83 deg before turning on the sump fan.
So I am putting the MH's on the 120 and the 4-65 PC's back on the 75.
The more water I am hoping in the 120 will let out more heat with the bigger opening on top for air and more volume of water.
If you are going to go with some of hard corals I would go 10K 250's I saw a big growing differance in all the corals. If you go all hard corals mybe someone who has 400 can tell how much heat they have all I know I not going to 400's the 250's ok for me it has alot of light and everything is growing well in the 120.
I read in the book The Reef Aquarium it is the inches of water the light that it has to go thought and 250's are good to 30 inches of water.
Also two ballasts if one goes out you have one to fall back on till you get the other one replaced,

04/29/2006, 10:20 AM	#1
tx_kyle Registered Member Join Date: Feb 2005 Location: DFW, Texas Posts: 10	Newbie Needs Help w/ MH Setup I bought an existing 120G (4x2x2) setup. The setup came with a 11" (inside measurement) deep canopy with two 400W Radium 20k bulbs mounted in a full length reflector. Unfortunately, one side of the dual ballast is kaput. I also don't know the age of the Radium bulbs. I've had 40G reef lite with 130W of PC lighting up and running for 17 months. Frogspawn, ricordia, sun coral.. easy stuff. I bought the new setup with the hope of hosting clams, BTA, and eventually maybe even SPS. As I see it, my options are 1) Buy a new dual ballast and keep the Radium 20k bulbs. 2) Scrape the entire setup and buy something new. Some random thoughts... 1) Given the tank is only 24" deep, 400W may be overkill. Seems like 250W would be fine and would cut down on heat generation. 2) Many people think 20k is too blue. I haven't seen enough examples to make my own judgement but, as a general rule, I'm sort of an "average" kind of guy. Also you have the consideration that some livestock (clams?) actually need a certain "color" of light. 3) My canopy is only 11" (inside measurement) deep. It seems that would preclude mounting a lower temperature MH fixture, say 10k, and then supplementing with VHO actinics or something similar. 4) I don't mind spending some money to do things right. I just can't afford to spend a bunch of money experimenting. Any advice would be appreciated. Thanks!

04/29/2006, 12:34 PM	#2
fishtk75 Registered Member Join Date: Sep 2004 Location: PA Posts: 1,530	I just upgraded to a 120 tank and had two 250's 10k on a 75. You are right about heat the 250's MH I have put out heat so if the one's you have the 400 will have more heat may have to buy a chiller. I had to put two Icecap fans on top to move the heat out and a third fan blowing over the sump to get more heat out plus it in the basement this was on the 75 looking at 83 deg before turning on the sump fan. So I am putting the MH's on the 120 and the 4-65 PC's back on the 75. The more water I am hoping in the 120 will let out more heat with the bigger opening on top for air and more volume of water. If you are going to go with some of hard corals I would go 10K 250's I saw a big growing differance in all the corals. If you go all hard corals mybe someone who has 400 can tell how much heat they have all I know I not going to 400's the 250's ok for me it has alot of light and everything is growing well in the 120. I read in the book The Reef Aquarium it is the inches of water the light that it has to go thought and 250's are good to 30 inches of water. Also two ballasts if one goes out you have one to fall back on till you get the other one replaced, Last edited by fishtk75; 04/29/2006 at 12:46 PM.