couple of questions about my setup

[J-dub]

My tank is a 55 gallon tank. I have two VHO's and for now one 400 watt hqi halide. (The other bulb is coming) The reason I have these is because I will upgrade my tank size in the near future so rather than buy new lights I bought the 400's.

Ok first off, even though some people thinks it's over kill I turned my lights on. I couldn't stand looking at them sitting on the floor not being used.............and I got a wild hair. There was nothing wrong my VHO's but like anyone else I wanted more. I set them up last week and since then have been running them 4 hours to start then every other day or so increase it about a hour. Just to get my tank use to it. I set the lights a wopping 13" off the water just to be safe. I mounted them with pulleys so I can adjust the hieght of them if needed. This is where I run into my problem my VHO's are so high they make my tank dark, but I suppose that when my halides are fulltime that won't be such an issue.

I have some hammers and a tourch coral should these be moved to the bottom of my tank? And what kinds of corals can I keep with these? I was told you can't keep hard corals with soft corals? Are these soft corals? Is my light too high? Should I add another blue VHO and get rid of the white one now I have my halides?

 

[ronj]

I have some hammers and a tourch coral should these be moved to the bottom of my tank?

i would move those to the bottom for a while..the 400w halides are for very deep tanks..they coiuld very well burn or kill these corals

Is my light too high?

the halides are fine that high..most people mount the 250w lights about 12" or so..i would say the VHO's definately need to be right over the water..i am not sure if the heat from the MH's will damage them though

 

[Krish]

Are you running the VHO's and the MH now or is it just the VHO's? If running both, for softy's I definately think it will be over kill...

 

[J-dub]

Here are some pics so you can get a visual. The last one is what I had before I mess with it.

Yes I am running the VHO's at the same time at the halides. You think I should run the halide only? I just like that the blue actintic light seems make the green really "glow" on my corals. Should I get a 12K bulb intead because I have a 10K now? I have just a fan blowing over the top of the tank and so far heat dosen't seem to be an issue. (fingers crossed)

 

[ronj]

that looks like a problem in the first pic....with the VHO's being mounted on the same fixture as the MH's, you can't move them closer..i really don't think you can put a 400w MH any closer on a tank that shallow!!! maybe someone else will know, but i think it will burn your corals and cause heat issues if it is any lower.

 

[Krish]

I'd run a higher kelvin rated bulb like a 12, 14 or even 20K and not use the VHO's on this specific tank. The 400 watts may still be a bit much, but atleast the intensity won't be as strong and also, you will get your blue spectrum in there without the need of extra wattage from the VHO's useage

 

[J-dub]

Huh, I always thought they needed the run at the same time for some reason. So have them turn off when the halide turns on and back on when the halide turns off? And a higher K bulb will give me the same effect as the VHO's?

 

[Krish]

Yup! You could do it that way for this tank. People only VHO's with halides for basically 2 reasons. One is for supplemental lighting (adding in some blue to make the corals look more appealing) when they are using basically white metal halide bulbs for better coral growth. The second reason is for a dusk to dawn effect where the tank won't be exposed to the full blast of lighting at the beginning of the photoperiod and then total darkness at the end, but rather Vho's in the morning (less wattage) metal halides a few hours later (with or without VHO's) and then coming towards the end of the day, just VHO's by themselves. If you look at the link below, you'll see what I mean about the different kelvin bulbs. Scroll down to the pics and look at how the same tank looks under different kelvin rated bulbs. The higher the kelvin rating (with just metal halides alone) the bluer the tank. HTH


http://www.cnidarianreef.com/lamps.cfm

 

[J-dub]

The higher Kelvin won't be as good for coral growth?

 

[KRG]

http://www.cnidarianreef.com/lamps.cfm

Awesome link!!!!

 

[Krish]

The higher Kelvin won't be as good for coral growth?

Usually not...I'm not a lighting expert by far, but from what I understand, the more PAR a bulb puts out, the more growth you get from your corals and the lower kelvin rating bulbs tend to have more PAR. Just look at the link I posted. A 10K XM bulb on a standard PFO ballast puts out about a 600 PAR rating whereas the 20K XM (same brand just higher kelvin rating) only puts out PAR rating of 242. Also, from what I understand, corals use the spectrum more on the whiter/yellower side than the "bluer" to grow and I'm not sure why that's so We need a lighting expert in here

Awesome link!!!!

Thanks! Try this one! It's even better! You get to change the bulb on one side of the tanl to what you want and put it up to another type on the other side of the tank to see the difference
http://chrismorris.ca/250wcolour/

 

[J-dub]

That link is really cool Thanks. I see what you mean about the par it seems to be higher on lower K. Personally, I don't mind the 10K compaired to some of the others. I curious to see what my bulb will turn out to be( it's only got like 20 hrs on it.) So could I use the 10K to get the most par for coral growth and use the VHO's to give it some blue and have both spectrums?

 

[Krish]

So could I use the 10K to get the most par for coral growth and use the VHO's to give it some blue and have both spectrums?

That IMO, is the best combination! Great coral growth and appealing to the eye. I guess it seems a little over kill running them all on your 55gal, but on your new tank, that would be real nice! That's the only reason I suggested going with a higher kelvin rating so you could love the look and not need to run so much wattage for now