lighting

[reavely]

I have a 75 gallon, 20" H tank with LPS, leathers, xenias, mushrooms in it - right now doing well with a 260W PC. I want to get a MH light. Looking at 2*150W MH + 2 110Wvho unit = 6.9W/gallon! will that fry my existing corals? will the whole tank have to be rearranged? how could I acclimate them to this intesity?

 

[reef fool]

You will need to acclimate them for sure, especially the shrooms!

 

[reavely]

what's the best way to do this? most of the shrooms have attached themselves to the top of large rocks that make it nearly impossible to place them at the bottom of the tank. On the other hand I would like to use the leg-stands of the new fixture and not have to set up the chain-hanging system and start high above the tank (I have limited clearance above the tank anyway) ????:help:

 

[flatzboy]

I would just run the vhos for like 12 hours a day and only run the metal halides for like 2 hours a day for 5 days then run them for 4 hours for 5 days then 6 hours for 5 days then 8 hours is the longest you should run them per day and always run them during the middle of the time the vhos are running.

 

[bang guy]

Raising & slowly lower the lights is best. Usually that's not practicle though.
Placing 3 layers of nylon screen over the tank will work. Remove a layer whenever all the corals look good & open - About once a week.

 

[reavely]

all great ideas -
Bang guy - won;t the halides melt the nylon screen? the stand I'm looking at buying puts the fixture 6" above the tank.
Flatzboy - the VHO's are actinic (I guess I assumed) how does that effect the process you describe - won;t the corals be starved for daylight, then SLAMMED with it when the MH come on?

 

[bang guy]

Of you've got a fan blowing on the water surface it will blow in the screen instead and prevent the screen from melting.
If you don't have that type of fan set up then let the screen material drape into the water to keep it cool. I've never tried that but it should work.

 

[reavely]

a surface fan?? never heard of it, obviously don;t have one. sounds like an evaporation accelerator

 

[bang guy]

Originally posted by reavely
sounds like an evaporation accelerator
That's exactly what it is.

 

[reavely]

wouldn't it be easier to air condition the room rather than cool the tank through evaporation? (if, i assume, that's why you'd want to accelerate evaporation). When the LFS guy here in NC tried to sell me a $500 cooler, I just bought a $99 air conditioner for the room - keeps the tank AND me cool

 

[bang guy]

That's great.
Those of us that use limewater to maintain Carbonate and Calcium enjoy increasing evap to get more of the good stuff in the water.
Cooling the room is excellent though! (ps. that increases evap too)