Building 72g bowfront hood - have questions...

[geoffs]

I am about to start constructing a hood for my FW 72g bowfront tank and before I start I am hoping to get some of the questions I have answered from the experts here...

When I bought this setup I ordered a 48" All-Glass strip light with electronic ballast controlling 2 55-watt, 9325K PC bulbs. With a total of just 1.53wpg I am a bit underlighted for the planted tank I want to have. My plan is to use the guts of the strip light I have in a new hood I will build, adding to it a 96 watt kit from ahsupply. This will end up giving me a total of 206 watts for 2.83wpg - much better!

Questions:

1. Given that I now have 110 watts of 9325K bulbs, what temperature 96 watt bulb would be best for me to buy? I can get 5000K, 6700K, or 10000K bulbs from ahsupply.

2. How should I position the bulbs? Should I put the 96 watt bulb behind (ie: towards the rear of the tank) the 2 55 watt bulbs? ...or the other way around? ...does it even make a difference?

3. Given that I now have a glass lid, how far above the lid would be best for the lights to be suspended? 1", 2", 3", or???

4. The 55 watt bulbs will be separately powered from the 96 watt bulb. What strategy should I employ in cycling the lighting? Just turn on all watts at once and off at once? ...or what?

5. I'm thinking of including moon lighting also - anything I should be aware of for this sub-project?

Newbie wanting to know what the experts think...

Thanks,
Geoff

 

[fishfreek]

Personally I dont like the quality of bulbs from AHSupply. Instead look for bulbs at ww.hellolights.com as for the spectirum I would say pick the specitrum for your color preference. The lower the K rating the more yellow will be in the light.

I dont think it will make much difference with the bulbs but with the 96W bulb being 3' in length it would probably fit best in the back and the two 55's in front of it.

 

[geoffs]

Thanks for the reply fishfreek!

Thanks for the pointer to hellolights.com - I'll check them out for sure. I take it that you've bought bulbs from both places and the ones from hellolights either lasted longer or were brighter?

As for the positioning of the 55w bulbs versus the 96w bulb - I was thinking I would position the 96w bulb at the front. My reasoning was that since it was 36" long it would fit nicely in the available space overhead the bowed area in the front of the tank. The way the two 55w bulbs are mounted (at least in the AGA fixture and I was going to duplicate that), they would have been too long as a pair for the bowfront area. However, I'm flexible if there was a good reason to mount things with the 96w to the back.

As far as height above the tank's glass top, I was going to go for about 4 or 5 inches. This wouldn't diminish the light intensity too much towards the bottom of the tank if I do this, would it?

Thanks for the advice...

 

[jerejohnson]

i dont know about deminishing the light but from what i can tell everyone for the most part doesnt use the glass tops because it traps heat and all that, but it should be fine with the top on. if your going to upgrade in the future you might consider leaving some room so that if you wanted to you could put a mh mogal in without having to make a bunch of moves. like if you mounted the 55 bulbs to the back and the 96 in the front leave enough room for a biger light in the middle? just an idea better to think ahead no instead of spending more in the end. good luck

 

[geoffs]

Hi! Thanks for the reply. I thought that this topic was just about on the dead heap, but it's still an active issue for me. I am much closer to building this hood and still have some issues.

I think that since I wrote that I wanted to mount the lights 4-5" above the water, I've been convinced by myself and others that I should probably instead mount them 2-3" above the water, just to avoid too much dropoff of intensity at the bottom of the tank.

As far as leaving room for an MH light in the future... hmm, I'll have to say that I can't see myself going to the MH lights. Being a systems software architect I pride myself on being able to design today for needs tomorrow. However, in this case I just can't see myself going there, but perhaps I'm just ignorant of the case for MH.

An open issue for me is definitely whether or not I allow the bulbs to be open to the water or above a glass or acrylic top. I was worried that leaving them open could be a bad thing for the fixture because of the moisture. I need some input from others on what their experiences have been in this regard.

 

[sumphead]

I just built a hood for my 72 bow and it turned out great. I'll snap a few pictures when I get home and post them. Probably within an hour or two. Actually I had planned on it for some time but procrastinated for obvious reasons, but I saw this post a coupla' weeks ago and it promted me. Post to follow...

R-

 

[yaksplat]

put an acrylic sheet under the bulbs. This will keep any water from splashing on the bulbs. If the sheet gets some salt creep on it just wash it off. This is the way i have mine and it's working out great.

Jim

 

[sumphead]

Well here are a few pics. It wasn't as difficult as I thought it would be. FWIW, I left my lights open, then again I am running MH and T5 actinics.

First thing I did was make a mask of the tank shape. I used 1/8" ply and laid it on top of the tank and traced the "bow". Then cut it you with a jig-saw. Then I decided where I wanted the piano hinge vs. the width if the lights. I basically built a box the size of the back portion with 1X2S and skinned it with the 1/8". For the front I think you can see from the picture how I used the 1X2s again with "L" brackets. When done I sanded, filled with wood putty, sanded again, and finished with a semi-gloss black. (Rust-oleum enamel)

HTH.

 

[geoffs]

Darn nice job, reefnewb! I like the simplicity of your hood and using 1/8" plywood solved any problem with shaping the front of the hood.

My design was going to use wood (and might still) but now I'm thinking I am going to make the entire hood out of acrylic. I have an ace up my sleeve on that one since my daughter works as a fabricator at a plastics store. She has offered to construct it for me if I provide the plans. I need to move on those plans...

 

[sumphead]

I am fairly handy with acrylic myself and actually considered it, but with Halides heat would have been waaaaay to much of an issue. I have two fans I need to install this weekend (waiting to buy a 4" hole saw) So far heat hasn't been an issue at all. Then again, the bottom half of the back is open and I run a 44" long sump fuge so the turnover rate is great as is the air exposure. I lose just over 2 gallons a day in evap. I'd love to see an acrylic job! I'll be waiting the pics.