70W MH Height

[slim]

How high should I get the 70W MH sentry Mod above a 20L tank? This will be in a hood. How much heat is generated?

Will

[cweber]

The bulb should be 6-8 inches from the surface of the water. I drilled some holes in my housing. (about six 7/8") I dont have any problems with heat on mine. The back of the hood is open w/ no fans. My tank stays a steady 81 degrees.

[dakar]

Are you trying to evenly light the tank with the 70w pendant? Think you'll find that 6-8" will only light up about 2/3 of the 20L if that. You may need to go a bit higher to get move even coverage. A 20L is a tough tank to light with a single 70w HQI, now a pair of them...that would be fantastic lighting.

[slim]

It will only be one side. I also have a set of 24" T5 that I will be putting in.

I am wanting at least 1/2~2/3 for SPS and the other 1/3 for LPS and softies.

Will

[dakar]

Don't be afraid of giving your softies the same amount of light as stoney coral.

Think there is a common thought that most non-stoney corals require less light.. That really is not true, most wild caught softies were collected in shallow waters and do very well under more intense lighting. While in captivity and captive bred, they do adapt to survive with less, but generally do not thrive.

I'm of the school of thought where I try to match the amount of PAR at 24" in the tank to that of 15 meters in the wild. Which in the case of the 180g tank means running 3x400w 6500K halides and 6x65w actinics. Worked out extremely well for us.

[melev]

I have a 150w DE bulb that is barely 3" off the water of my new angled tank, but soon it will be higher as the cables arrived over the weekend. I have to find a couple more parts, but I think I have everything to suspend the fixture at last.