400 watts halides

i dont think i would run a 400 watt with out a chiller on that tank. i think a 250 is all you need in my opinion. or you could do 2x150's(would be my personal choice)

now a halide will only cover 2 square feet so you would have one area in your tank be a high light area and the rest be lower light.

 

I WAS refering to me liking the blue from the 20k and using 420 and 460nm T5s ("I like it bluer"). If it isn't a preference of liking bluer, then "I would go with what Tangster said and do a 14-15k"
... sorry, maybe I wasn't clear.

 

Your energy co must love you.

2x250 is perfect on a 90g, and I run 2x54 of t5ho .

400w halides are pretty much wasteful for any tank unless it is like over 3 feet tall.

Watts don't mean anything to coral, but PAR does.

 

You honestly run that much light over a 90? Why use three MH when 2 would cover just fine? Just not sure what the motivation is.... I have seen less wattage on 180s

 

Tang,
I think these say it all, 3x250s on a 190...
A guy in our club...

 

If just 3. 250's on a 190 then you can imagine what 3. 400's on a 90 are doing ..

 

You have some pics?

 

I'm in charge of picture taking and I've been slacking in that department. I'll see if I have some time to take some this weekend.

 

Joe, Johns actually switched to 2 x400 SE's from the 3x250 halides in those pics. He is running 20k bulbs IIRC though. Please keep in mind that johns, the guys tank above, has a 5 foot 190g. he had great growth and color on his tank lit by 3x250, but he went to 2 x 400 because he could since it is only 5 foot long, and because it would save him $$ at bulb changeout time. He also wanted the PAR values, while having a very blue tank.

I don't have par #'s for my 90g, but it is plenty bright I can say, even with crappy reflectors for my halides. There are folks with very good growth with 2x175 on 75g tanks, and one guy with 2x175 on a 90, all will t5s to boot.

I assume you must be using a very blue spectrum like 20k to be able to run 3 on a 90g.
Also, you can have too much PAR and it creates photo inhibition, actually making the corals less happy and grow less.

Do you have PAR #s on that 3x400 lit 90?

 

Nope