Adjusting height of light for light spillage

[kinetic]

How do you adjust your light height off the water such that you minimize the amount of light that "spills" from the tank?

I put my hand next to the lip of the tank on one side of the tank (not the front or back), and lowered the light until my hand got dark. It wasn't clear cut, but it did get considerably darker at some point. I started my light at 18" above the water, and now it's about 7" above water level.

It's a Hydra 52 HD over a 24" x 20" x 20" tank. I'm pretty sure the front is still getting plenty of leakage, but the sides are good.

Is 7" about right? I think the light is probably well sized, if not oversized, for my tank dimensions. The downside is maybe that makes me need to hang it pretty dang close to the water. I wish I could hang it higher.

 

[kinetic]

Here is how high it was before. Looked good. Don't have an updated picture, but now it's more than halfway down from the original position.

 

[SashimiTurtle]

7" sounds like a good number for that tank. If the light is hitting close to the top of the rim on all 4 sides, then you know you have pretty good spread. Just keep in mind that you'll probably have a hotspot directly under the light to about 12" water depth.

 

[kinetic]

7" sounds like a good number for that tank. If the light is hitting close to the top of the rim on all 4 sides, then you know you have pretty good spread. Just keep in mind that you'll probably have a hotspot directly under the light to about 12" water depth.

My rockwork is pretty far from the top of the water level, and a hotspot might be OK. Maybe an anemone will find it's way there

Thank you!

 

[SashimiTurtle]

I've got my Kessil A160 about 7" from the waterline. It still spills over, but I have a really narrow tank... it's 20x12x13...

 

[SashimiTurtle]

Or is that 12x20x13?

 

[kinetic]

Is that the Fusion peninsula? Looks nice.

 

[SashimiTurtle]

Is that the Fusion peninsula? Looks nice.

Yes, it's the 14g with the APS stand. Hindsight, it's too narrow and shallow. It's a great little tank and very well built. The seams are flawless, I just can't bring myself to put fish in it. It's home to a coral banded shrimp, a pom pom crab and a few snails.

 

[kinetic]

Yes, it's the 14g with the APS stand. Hindsight, it's too narrow and shallow. It's a great little tank and very well built. The seams are flawless, I just can't bring myself to put fish in it. It's home to a coral banded shrimp, a pom pom crab and a few snails.

It looks so great. I would totally get one and just keep a garden of zoanthids and a few snails! I actually had a small 4 gallon custom acrylic tank that was just two snails and a bunch of zoanthids. It was fun! My water changes were simple, just a few cups from my main display tank every week

 

[SashimiTurtle]

Heh, this tank is actually SPS dominant. Acros, stylo, birds nest, digi, duncans and acans. One tiny 4 polyp frag of rastas in there tho. Oh yea and a small rainbow BTA.

I'm upgrading to a 90 cube next year sometime and this is my learning tank. Plan is for an acro and acan dominant tank with that one.

I might sell this one, or go extremely low maintenance zoa garden or something. Probably just sell it to recoup done money for the 90 build.