DIY Light hood/canopy

[woodendude]

I'm in the process of building a lighting hood for my aquariium and was wondering are there any advantages/disadvantges re: the height the bulbs are away from the glass top of the aquarium and also the distance the bulbs are placed apart within the hood. The hood will be on a non planted cichlid tank but hope to switch this tank SW in the near future.
The bulbs are shielded, 72" one daylight one atanic blue, not sure of the wattage.. Oh and I guess I should ask if there is any harm in usingh what is traditionally SW lighting on a FW tank?

Thanks,
Derek

[kennyman]

The needs of a SW tank range from the single tube 1wpg of typical FW setups for a fish only SW tank to 250 watts of Metal Halide for every two feet of footprint suggested for a SPS dominated tank. The question of how usefull your cichlid tank lighting will be in a SW tank just too vague.

[BigDaddy]

As far as distance between bulbs goes it depends on if you are using dedicated reflectors or not.  Without reflectors, bulbs that are too close together cause restrike, a condition where the light from a bulb hits another bulb or reflects off a surface and hits itself again, which causes the bulb to heat up and become less effecient.  To a lesser extent, restrike can also increase the temperature of the air inside your hood which can in turn heat up your aquarium.

[Aquaviewer]

You have to consider what sort of venting you are going to have.  As you increase the wattage/number of bulbs you are going to have to install a fan(s) and provide adequate venting for return air to enter the canopy.  Also you have to allow sufficient room for access and maintenance.

[woodendude]

My plans call for 2 80mm. computer fans pushing air out the back, and a slotted top on the canopy, would this be adequate do you think?

[woodendude]

The box itself is going to be  72" l x 7.5" h x 10" w. it will only house the 2 bulbs,2 workhorse 7 ballasts .

[woodendude]

The bulbs are URI bulbs  165w per bulb total of 330w, this will be more then adequate for my FW, but will it do if I go over to SW IN 130 gal.?

[kennyman]

I think that it will give you a good start with low light demanding corals when you change over to a reef. But as you want to get more light demanding corals you will want to add to it. As a comparison I run 130W over a 2' tank and only stock medium light LPS and softies. I cant do the Acro's or light hungry clams.

Leave room to double it up if you can. Is this the bulb with the built-in  reflector? Sure sounds like a nice setup to start with for sure  .

[woodendude]

Kennyman,
                By built in reflector , do you mean the bulb only projects light out the one side?, if yes they both are. I actually just finished putting my box together today and am sad to say I won't have room to double up in the future. But this isn't entirely a bad thing as I learned a few things doing this one that I'll not do to a future box when the time comes to put one together.

[woodendude]

As you can probably tell by my questions here I know next to nothing about this stuff. I've had aquariums and fish of course for a few years but never went any further then the standard sold as a kit set ups. I've know problem keeping my fish alive and happy but this is a new adventure for me. So here goes another possibly dumb question, does the placement of the bulbs have any order that should be followed for best results ie: blue in back, white in front ?