500Watts Halide on 55gal. No Shimmer?

[Marsfrogie]

As the subject states. I just recently got two 250 watt HQI XM20K halides for my 55 gallon aquarium. I have them running on electronic ballasts from hellolights. I've got a couple of questions/concerns.

1. These lights are very bright, don't get me wrong. But I was expecting a little "more" as I was upgrading from 260watts power compact.

2. There is very little shimmer effect going on. The glass shield on the reflector is 3.5" off the water's surface. The actual bulb is around 4.5-5" off the surface. There is a slight shadowing effect near the center of the tank that is annoying me slight too. I don't know if I could make it benefecial or not.....

3.If I go higher with the bulbs won't I lose intensity?

I don't know, go shoot. Thanks.

[raynist]

Do you have much surface agitation of the water? This is what makes the shimmer lines. Your eyes may not be able to see the difference, but I am sure you have much more par.

[Marsfrogie]

I've got about 1680GPH running in the tank. You can see the surface move but it's not near as much movement as I've seen on some people's tanks.

I see that's 30.5GPH Per Gallon. How's that rank in comparison to other tanks?

[Marsfrogie]

I forgot to mention. I have a significant amount of shimmer under the lunar light. So there is adequate flow to generate shimmer. Also, with the halide there is noticeable shimmer on the walls next to the tank.

[reefkoi]

I'd back that bulb off to about 8 inches above water and see what happens, I have to have a lot of flow right on the surface creating 1/2"+ ripples to see a good shimmer.