Question about T5 lighting

[cmc0814]

How high off the water should my lights be? I have a Tek T5 hood with 6 - 4' lamps in it. Right now I would say it is around 3 inches off of the water, and it is making my tank very hot. I have seen it get 85 degrees. And with my PCs that far off the tank, I didn't have any problems with heat. So I'm hoping that I could raise them a little. Thanks!

-Chris

 

[abigdog1976]

We have 14 bulbs right on the 175 tank and the water stays 77 - 78 the 8 bulb fixture sits about 8 inches above the water and that one gets up to 80 (it appears the Tek light fixture puts a lil more heat than the aquatinics brand)

 

[pwhitby]

Chris, I would place a fan to blow between water and lights to remove some of the heat.

3-4 inches is fine. Mine are at 5

 

[papagimp]

I have to keep my tek light about 8-10 inches off my tank to keep from cooking everything. Oddly enough, If I put it any closer it appears to give too much light intesity for my corals. (55g) Everyone shrivels up and my euphyllia start spitting out lots of zooanthelle (however its spelled)

 

[captbunzo]

<a href=showthread.php?s=&postid=8224546#post8224546 target=_blank>Originally posted</a> by papagimp
I have to keep my tek light about 8-10 inches off my tank to keep from cooking everything. Oddly enough, If I put it any closer it appears to give too much light intesity for my corals. (55g) Everyone shrivels up and my euphyllia start spitting out lots of zooanthelle (however its spelled)

That actually makes a lot of sense, papagimp. T5s are relatively equivelent in punch as corresponding Metal Halides. And with LPS and softies, you may actually be a little overlit. Now, that's not a problem, as you have solved it by raising the light.

As for all the heat problems, that's pretty interesting. Mine don't seem to overheat things in my canopy too bad.

 

[papagimp]

Do you have the Tek light fixture? I have a hunch this particular fixture may just heat up more than most. My power compacts didn't heat up this much, Just putting your hand beneath the lights and you can feel the difference. May be the fact that instead of seperated individual reflectors, the tek light fixtures use a single reflector bent to individually reflect the different bulbs. Did that make sense? Anyways, this would cause heat exchange differently than if each bulb had a seperate reflector. Just my thinking outloud though.

 

[pwhitby]

I have the tek ballast with individual reflectors. Its mounted on 3/4 pvc with eggcrate, so its a very open structure. Mine doesnt get hot at all.

paul.