[RobG]

Any opinions? I'm getting rid of my JBJ PCs for my 90 and going to add dual MH, one on each side of the center brace. I want to keep clams, sps etc... and I know 220w of PC is not going to cut it.

Should I get dual 175, 250 or 400? I'm leaning towards 250

[organicreefer]

sps ,clams eh,definitely 400's.if you cant afford the e- bill i think maybe 250 hqi's.either way dont forget youre actinics!

[scubadude]

I personally would NOT go with 400's unless you want to run the risk of having to buy a chiller! Im using 2 - 175w MH 10k along w/ 2 - 48" VHO actinic strips on my 90gal and I will tell you that I have been peaking out at 82 degrees....which I think I would be running into some major probs if I got much hotter than that....Im NOT using a chiller and my corals (lots of SPS, some softies and lps) are all thriving...so are my clams! I have 2 - 4" Radio Shack fans built into my hood and have at the opposing end a large piece of eggcrate (serves as a vent).....So my point on a 90gal is to try not to go overkill on your lighting....Unless you have alternatives for handling heat issues. HTH Good Luck!

[organicreefer]

as long as you mount youre lights correctly(at least ten inches above the water)and have fans,heat shoiuldnt be a problem.ive been using 400's since the get,and ive never had a problem with heat.

[RobG]

I certainly cannot afford a chiller right now, so heat is definitely a concern once I add MHs. Though the tank is kept in the basement which stays cooler all year round than the first floor.

It seems that both of you are having success at the opposite ends of the lighting spectrum (175 vs 400). Maybe in the middle is the way to go... especially considering that running 400s will cost a good deal more on the power bill than the 250 or 175s.

I haven't built/bought the hood yet, so I can be flexible with how high I mount the bulbs. Scuba, how far off the water surface are your MHs? OR, what temp do you keep your tank at? Are your MHs suspended or retro'd into a hood?

Anyone else with a 90 want to weigh in?

[organicreefer]

rob,
i have a canopy with no top my tanks stand is about 39 inches tall and the hood is way higher than you can see so it doesnt matter.i run my tank at 80 degrees.im building my hood for my new tank and it will also have no top(its the way to go ,imo).all hid lamps are gonna transmit their heat if the are about 9 inches or closer to the water,sure 400's produce more heat ,but mount them correctly,and heat really isnt much of an issue.also it is a 93 gallon tank.

[Ironreef]

My 120g with a 49sump with a 10g refugium thats in a cool garage with 2 mak4 pumps had 4 maxijet1200 always ran 84-86 no probs. My lighting was 2_250w 6.5.. 3 actinic vho. Tank is acylic in a wall with halides 8" above. i don't like them to high. But I took out the 4 maxijets and my tank runs 80-82 average. When I put an ampmaster on it may run coolor?? But I would have 400w if heat wasn't an issue. But fwiw I've seen nice tanks with 175w and just vho with sps. Some sps do well without 400w. Personally I prefer more lighting but the heat and the $$ for power wasn't an option. But since my tank is coolor I may put another halide. But IMO I would go with 250w at least. Especially if your tank is glass. Doesn't hold the heat like acylic

[organicreefer]

rob i wanted to second what ironreef said,go with at least 250's.i have a dual 175 setup a 400 and a 250 setup.ime everything does "better " under the 400's(1000's are even better i bet).something about the "intensity ",i dont know.maybe just my imagination,but even with equal total wattage,there is still something about the intensity of the larger arc tubes in bigger lamps.

[organicreefer]

Originally posted by Ironreef
But fwiw I've seen nice tanks with 175w and just vho with sps. Some sps do well without 400w.

i would totally agree with this statement,but add that SOME sps will never color up the way they should without it

[Ironreef]

I just got a nice polcipora(sp) frag from a 75g. The lighting was 4_40w no lights. It was brown with a tint of green. The green is getting brighter. But his tank has many sps. Kept well over a year.Not really hard to keep species. But I could never keep sps in vho. He said he's get vho probally= will color up nicely. He has a huge refugium= probally getting its food source from there. But I seen sps color up under more lighting and haven't been able to keep any in other than halide. But there some ppl who can.

[Nanook01]

You could get the best of both worlds by using the HQI 250w pendants, more PAR than all 400w bulbs except Iwasaki. For that size tank, you would have more than adequate coverage with the mini-pendants.

FWIW,

Nanook

[RobG]

Due to asthetics and my girlfriend complaining about nothing covering the fish tank, I have to get a retro into a canopy, I can't do the pendants.

I do have a glass tank, and like I said, the basement is relatively cool (especially in the winter -- it's chilly down there) so I'm basically looking towards 250 or 400. I think it's going to come down to cost. If I'm buying new, they appear to be very close in price, so I'll probably go 400. I've been looking here, PA, champion lighting for prices -- any other good places to look?

I'd far rather buy used or ebay or something, so I'll probably get whichever I can do for a good price -- it sounds like either would be OK.

Do you have any pics of that "open top" hood organicreefer?

[golfish]

Rob,
Any canopy that will house MH's will house the 250 watt HQI mini pendants from PFO. If it were my tank and knowing what I know now I would use 250 watt Iwasaki's with a PFO dual standard ballast on your tank. Changing out the white 55 watt PC's for actinics will make the tank look very nice.

The HQI's will cost you more $ and have the same par as the 250 watt Iwasaki's. The color might not be the best but the PC's will help out there. You'll want to use the PC's for a dawn dusk effect anyway.

The 250 watt Iwasaki will out do all but one of the 400 watt bulbs (400 watt Iwasaki) It will match the HQI's when the UV shield is used (must be used at all time)

Another option would be to use 20k 400 watters on a PFO HQI ballast. They say the color is the best of all the bulbs.


Mark

[scubadude]

Originally posted by golfish
Rob,

The HQI's will cost you more $ and have the same par as the 250 watt Iwasaki's. The color might not be the best but the PC's will help out there. You'll want to use the PC's for a dawn dusk effect anyway.

The 250 watt Iwasaki will out do all but one of the 400 watt bulbs (400 watt Iwasaki) It will match the HQI's when the UV shield is used (must be used at all time)

Mark

HUH?!?! Mark you totally lost me on these statements! are you sure you didnt get it backwards? Here is a Quote directly from Sanjay Joshi and Dave Morgan's analysis report on the spectrum outputs and PAR ratings. This test is on the 250w ONLY!

If you subscribe to the “more PAR is better” theory, then obviously the best choice is either the double-ended 10,000 K lamp or the 6500 K Iwasaki lamp. If you subscribe to the “more blue is better because corals are found in water where the higher wavelengths are filtered out” theory, then it’s worth noting that the 6500 K Iwasaki lamp had higher output in the violet/blue range than the 10,000 and 20,000 K Coralife lamps. The double-ended 10,000 K lamp is the best combination, offering both the best PPFD and the more blue color many reef hobbyists are interested in.

To read this report ( I Highly advise then here is the link )

Sanjay Joshi's 250w spectral analysis report