PC to metal halide....what to choose? help

[Mbeef61]

i have a 135 gallon tank that the dimensions are 72in long, 24inches tall, and 18 inches deep. i currently have 4x96 watt power compacts (there are 2 36inch fixtures) one on each side. i want to change to metal halides i was thinking 250s. how you would setup a tank like this if you could do it. i dont want anything crazy i like the look of the most natural possible. would you use 2 or 3 250s? i thought i could gut the 2 2x96 fixtures and run 4x96 watt power compact actinics. also what would give me the closest thing to natural sunlight? 10k? 14k? what do you think any suggestions are needed. how high off the tank?

i was thinkin keeping it smaller not a fully loaded system so i wanted to keep it to 250s. i am running a smaller DSB. its approx 3-3.5inch thick so that puts my water depth at about 20-21 inches. right now i have a pagaoda coral thats thriving under current conditions. various mushrooms and plate corals and starpolyps. i would like to keep a few SPS and definately a clam. where would you put a clam with this setup. About a 5ich super crocea.

 

[Brenden]

You are going to need 3 mh fixtures. They are made to cover a 2X2 sq ft area. If you are happy with the current brightness of your tank you may want to consider 3-175W. Your corals will not like that much change going to 250W. You will have to work them into it gradually. I recommend 14k bulbs since you are not running antics with it. They give off a nice white light with a slight blue hugh. Most (acrylic) tank manufactures require MH lights to be 8 inches from tank to keep warranty. HTH

 

[lando]

For a 72 gal I would go with two MH lights. Three would put one MH lamp directly over the center brace therefore rendering it pretty much useless. Brenden is correct that MH cover about a 2x2 area so two in a 4ft tank will be just fine. As far as wattage goes, it really depends on what you plan to keep. There is really not a lot you can not keep with the 4x96watt CF. Stepping up to MH will allow for more SPS corals and clams. I just purchased a MH fixture from www.aquatraders.com and am happy with it. If you are not a DIYer, it may be an option for you. I got the 2x175watt MH with 2x 96watt actinic. As far as bulb K goes, it is really a matter of personal preference. 20K will give you a crisp blue shimmer to the water while 6500K or 10,000K will permote the fastest coral growth but will look more yellow, so more 03 suppliment may be needed.

where would you put a clam with this setup. About a 5ich super crocea.

The corcea is a rock dwelling species so it should be kept on the rock work. Find a flat spot for it to attach and make sure there is plenty of room for it to open, expand and grow. It can be kept in the sand bed as well but I recommend burrying a flat rock in the substrate for it to attach to.

 

[Phyl]

72=6'... Um... I also think he'll need 3 fixtures to cover the 6'. 5' would be debatable, but at 6 I'm all but certain you'll need 3 to cover it effectively. Are there two center braces or just one? If you only have one brace then I'm not sure what I'd do as I wouldn't want a MH directly over my center brace. One of the guys in my reef club is debating this issue now.

 

[Mbeef61]

i have one single center brace. (its glass so its ok. its a catalina tank i wouldnt recommend them to anyone..the first one cracked!) so yeah there is one center brace but its about 10 inches wide but its glass. the same thickness as tank itself

 

[greenmaji]

honest mistake lando.. its 72 inches long.. not 72 gallons..
Im intrested in the wattage you recomend for a 135 gallon tank.. just to get better idea what MH can do..

 

[lando]

honest mistake lando.. its 72 inches long.. not 72 gallons..

My bad...I must have read too fast.

 

[DragonForce]

2x400's 14k placed ~18 above the water IMO. Then you won't be limited to what you can have.

 

[greenmaji]

I would run VHO's or T-5 HO's in the middle over that brace..
I wouldnt run any 03 or just one for SPS.. I would go with 12000K and 11000K or 10000K.. and maybe 1/4th of the bulbs 03.. for lower light more 03 up to 2/3 of the bulbs

at 20 inches if its SPS and clams.. 2- 250watt MH on the ends.. if its LPS, softies and shrooms go with 175's MH.. if your not going to supplement.. 14,000K seems the way to go right now..

 

[Brenden]

Everyone I have talked to that has 400w mh hated them and changed them out. Maybe someone is here who likes them? I went with 250w HQI pendants because of the issues with 400w lights

 

[revhtree]

I concur with 3 x 250w for the tank. I have a 6ft and just made the switch. The coverage is perfect and there is nothing like MH's!!

I got 3 retro fits, with 15k xm bulbs, plug and play for $470 shipping included.