MH placement

[jimsha]

I was wondering how high I should mount MH lighting from the water? I have a typical 90 gallon tank. I am getting 2-250W MH retro light kit. Any suggestions?

 

[snulma1]

Most people mount theres about 6-8" from the water surface

 

[michaeldaly]

I have mine 6in but they are 150W. For250W I would say 8 in.

 

[george1098]

yea 6-8 sounds good. I would hightly recomend using some sort of a water sheild. maybe a 1/8" peice of clear acrylic. some people moan about how it would reduce the amount of light that hits your tank, but i think a 1 or 2% reduction in light intensity is far prefferable to fishing out shattered glass shards from your tank and loosing all your corals to UV exposure because your bulb exploded.

 

[Musho3210]

<a href=showthread.php?s=&postid=10109186#post10109186 target=_blank>Originally posted</a> by george1098
yea 6-8 sounds good. I would hightly recomend using some sort of a water sheild. maybe a 1/8" peice of clear acrylic. some people moan about how it would reduce the amount of light that hits your tank, but i think a 1 or 2% reduction in light intensity is far prefferable to fishing out shattered glass shards from your tank and loosing all your corals to UV exposure because your bulb exploded.

I agree, if you clean the glass every so often with RO/DI water you shouldnt lose too much light.

Will you have fans with this fixture?

 

[george1098]

yea, i made my water guards so they slide out easily for cleaning. i clean every 2 weeks or so. i recomend putting two fans on you hood, one blowing in, one blowing out. you can get 3" computer fans really cheap on e-bay.

 

[jimsha]

thanks everyone for the input. Yes I will have fans..and why would the bulbs break?

 

[george1098]

I have seen them break before. I assume it is because splash or mist from the water hit the bulb while it was running super hot and cause the glass to crack, and eventually break. They say the the single ended bulbs won't break anymore, but i don't want to leave it up to chance.