Light fixture for a 12 gal tank.

MONARK

Junior Poster
Sep 9, 2009
2
0
1
Hi,

I'm planning to set up the GLA 91-B tank (36 x 8.3 x 9.4in), this tank looks very thin and shallow plus it will get shallower once I added the two or three inches of substrate.

Link:
http://www.greenleafaquariums.com/glass-rimless-aquariums/rimless-aquarium-91-b.html

My plan is to make an Iwagumi style scape. The tank will have two to three inches of ADA aquasoil of GLA's substrate system, a couple of rocks here and there and will have a carpet of Eleocharis Sp Bellem only, will add also CO2 through inline diffuser connected to an Eheim 2215 and ferts dosing.

I pretty much have anything planned except for the lightning and here are my doubts:

1. I have looked online and can only find 36" T5HO's fixtures with two bulbs, 39watt x 2 for a total of 78watts and that would be too much over the 12 gall tank and I do not know if I could be able to run just one bulb and leave the other socket emptied and the fixture would run fine or should I just run both bulbs but raised the fixture like 12" away from the tank.

2. If I could run only one bulb the tank would have 3.25wpg and I've read that small tanks need more light than usual so I was wondering if there would be enough light to grow a nice thick and curly carpet of Eleocharis Sp Bellem.

Need sugestions.

Thanks
 

jonny_ftm

Guru Class Expert
Mar 5, 2009
821
2
16
You can go with 2 Arcadia Arcpods, I'd say 11W each rather than 9W as your tank is really long. However, PC light on such a short in depth tank can be excessive. You put each one on a side (right/left). You can angle them using some plastic transparent clips to get a better diffusion of light. The center will get less light, so you'll have to adjust your scaping with that in mind (anubia nana petite, moss...)

Look at my 12 gal in signature, but yours is double length of mine and 8cm less in height

Best go would be some hood you make your self or back wall brackets to attach some kind of PC light (I think arcpods can be attached to a wall) so that you can adjust the hight of light
 

MONARK

Junior Poster
Sep 9, 2009
2
0
1
I don't think the Arcadias could be an option since the tank is 36" and the arcadias are only 11 3/4" long a third of the tank's length... the only option that I see is to use the 36" T5HO 78watt and hang it and play with the distance between lights and tank until I get right, I can not think of another option.

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Left C

Lifetime Members
Sep 26, 2005
2,500
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Burlington, NC
You could get a 36" single bulb T8/T12 fluorescent fixture that comes stock with some aquariums and remove it's guts. Then add a single bulb and reflector for a DIY 39w T5HO. You can get either IceCap or Sunlight Supply parts, reflector and either a Fulham or Advance ballast.

Here's a bit more specifics. IceCap makes a two bulb kit that doesn't have the reflectors or a ballast. Then you could get an IceCap or Sunlight Supply reflector and your choice of ballast. Here's the IceCap kit that I'm referring to and, of coarse, some parts won't be used: http://www.marinedepot.com/IceCap_T...etrofit_Kits-IceCap-IC1311-FILTRTRFT5-vi.html

Then you could suspend it, if you wish. You could also paint it black or silver or whatever color that you want.
 

jonny_ftm

Guru Class Expert
Mar 5, 2009
821
2
16
2 arcadia will provide more than enough light once angles at some 30-45° even in center area. PC light behaves like T5. Now, you have to like their look, I can agree, but they're not that ugly at all. Your tank is too short on depth and 78W T5 will "burn" it or you'll have to hang it extremely high --> ugly and so much light/electricity lost + eye blinding effect whenever you look at the tank. A 25W T8 is a good option though, but you'll have to mod/make the hood