Lights Issues

[BrianT]

Ok, long story coming.

I built a rack to sit above my 150 gal tank (48x30x24). I had some ballast that I though were mogul base, which I bought 2 175 watt 14k bulbs for.

I discovered it didnt fit the ballast and I cant find a 150 watt medium bulb that would produce decent lighting for medium to high plants.

I started off originally with two PC 65watt each 6700k (7 out of 8 bulbs are 6700k). My fear was that these two PC lights wouldnt be enough to penetrate the depth of my tank to give decent ground to ground cover.

Now I'm back to square one, with 5 bulbs I bought and three ballast I probably wont use.

I think the calculation is right , comes out to 3.5 wpg with the two PC's on there.

Suggestions?........................

[dbosman@msu.edu]

Post the details or specs on the ballasts so someone can give you an informed opinion.

[Hoppy]

First, don't worry about watts per gallon. It doesn't mean anything. I'm not sure if your tank is 24 or 30 inches high. In either case the PC bulbs will provide plenty of light, but only in a swath of substrate under the single line of light fixtures. Your big problem is not that the tank is too high for the light to penetrate to the substrate, but that the tank is to deep - front to back - for the whole substrate to be lighted by a single row of any kind of lighting. This is where using multiple 1 or 2 bulb T5HO fixtures, each 48 inches long, would work a lot better. You would want to separate those multiple fixtures by about 4-6 inches, so 4 or 5 fixtures should be adequate. I think I would use 2 bulb fixtures, so I could raise the fixtures a few inches above the top of the tank to get more uniform light intensity all over the tank.

If you go ahead with MH lighting you will need a pair of the lights, but I have no data that would help to guess what the light intensity would be for any given fixture.

[BrianT]

The ballast are 660 watt 250 volt single ballast. They were grow lights before we seized them during a drug case. I'm so friggen uneducated about a planted tank that I'm embarrased lol.

I may just invest in some decent T5's , just have to keep it on the downlow from the wife lol.

[lauraleellbp]

You possibly could sell the MH lights; they'd probably be great for someone setting up a SW tank.

If you can sell them you probably should be able to cover if not at least defray the cost of new T5HOs.