? is this low or moderate lighting

[pitmindi]

Hi, I started my 90 gallon tank 3 months ago. Recently I added many LPS corals. I also bought a new light. Do I have moderate or low lighting? I need to know so I can determine where to place my corals. My light is an Aquatic Life Light 48" T5 HO 4 Lamp. It has (2) 48" T5 HO 54W 420/460 Lamps, (2) 48" T5 HO 54W 10,000K Lamps. (4 bulbs, 2 white & 2 blue, 222 watts total) I have a 7" deep sand bed, so the sand bottom is 19" from the top of the tank. My tank is 18" wide and 48" long. The light fixture is on removable legs so it is about 4" above the top of the tank. I could lay the lighting unit directly on top of the tank, but it might make the water too warm, especially in the summer.
Which bulbs (the blue or the white) are better for the coral?
How long should the white bulbs be on each day and how long should the blue bulbs be on?
Can I place any of the corals on the sand?
Would corals that I place in the middle of the tank be considered moderate lighting? What about those placed towards the top of the tank? Would you please tell me where to place the following corals: frogspawn, hammers, bubble coral, red cynaria coral, neon candy cane, red/green favia, aussie acan, zoanthids, mushroom coral, green star polyp, and a neon green open brain. THank you so much for your help. I am a newbe and need some expert advice!

[pitmindi]

No Help Yet?????? Where are all the experienced reefers??? Have I stumped the experts?

[anathema]

Borrow a PAR meter. :)

[mscarpena]

I would say moderate lighting and low on the bottoms and sides. A PAR meter is your best option, but not all of us have that option. You could probably put some acans, mushrooms, dendros, or blastos on the bottom.

I keep my lights on for about 9 hours per day.

Do a mix of blue and white bulbs, but bluer bulbs put out less par usually.

[Reef Bass]

+1 for your setup being mod - low lighting. I was running a 6 bulb T5 fixture 8" over my 12" deep lps tank but it was too intense for lower light loving lps. I removed two bulbs and am now running 4 bulbs (2 blue, one daylight, one purple).

The favia and brain would be on the lower light end of your critters. Yes you can put things on sand as long as the lighting and flow there is good for them.

[THE JOEY]

+1 I agree with Reef Bass. Mod-low. I have a 6 bulb t-5 fixture over a 40g.

[sedor]

Your definitely going to be limited with only 4 bulbs over a 90. When I was looking for T5's over my 72 it was between a 6 or an 8 bulb fixture. Also, with T5's, reflectors are a big deal. You could greatly increase the performance of 4 bulbs if they each had individual reflectors.

I'm not saying you can't keep anything with your fixture, because there are plenty of choices you could keep, just don't expect to house clams or sps and even some of the higher light dependent lps.

[pitmindi]

Thanks everyone. The bulbs do have their own reflecters. The unit has 2 fans. Can I lay it directly on the glass cover for increased lighting? Currently it is about 3" above the glass using the extender arms that came with the unit. Also, I have frogspan, hammers, bubbles, candy cane, zoa, mushrooms, a favia and an acan. Can any of these be placed directly on the sand? Everything is now either on the top or in the middle, due to my lighting concerns. THANKS FOR YOUR HELP. The issue of lighting is very confusing for me. I still dont understand what is better for corals, the white bulb or the blue bulb. And 10,000 vs 6500...I just dont understand all this and its relation to my tank

[rogersb]

Lose the glass lids, they will cut down on the light your coral are getting. I'm not a lighting guy, I don't know technical stuff, only enough to get by but I have a similar fixture. I have it about 3 inches off the water. my tank is 60g but with your sandbed our height should be relatively similar. I am currently growing out several chalices on the bottom to mid level, frogspawn, hammer, blastos, and elegance on the sand, and 10 or so medium light SPS halfway and up.

Like I said, I'm not a light guy, but if I were you I would get rid of the actinics and go to reefgeek and get yourself 2 blue plus and 2 blue special. I really like the combo and my coral are getting bigger by the day.

[Gold Stripe]

Really depends on the bulbs and the ballast driving them but "generally speaking" the whiter the light the more growth you can expect but less color will show. Bluer light will bring out the colors more but will not be as intense so will not foster as much growth.

[Maivortex]

You have medium lighting. U could keep sps on the top 5 inches of the tank.