Lighting my Rimless Tank... WIDE rimless tank

If you hang that 4 bulb fixture a foot or a bit more above the top of the tank it should work fairly well. I think a better option would be to contact Catalina Aquarium and have them make a custom light, using a 12 inch wide housing, with two bulbs at the front and two at the back, 4 total T5HO bulbs. Then hang that about 8-10 inches above the top of the tank. That should give you very uniform lighting.

I run the 24" 4 bulb fish need it T5HO over my reef tank and it's too much light for even some of my lower light coral, which needs waaaay more light than any freshwater plant unless you have crazy CO2 injection and ferts.

I think a 24" 4 bulb fixture hung high over the tank would make a nice even spread. What Hoppy said would work great, it would just cost more.

But hanging a fixture the same length as the tank that high above the tank will cause a lot of spill over. So I might go with a 24" 4 bulb fixture hung above the tank to allow it to spread out nicely.

I agree with Hoppy on the Catalina. They are having some problems on their website but I talked to John and he said it should be fixed soon.

I just ordered a custom retrofit from them (47"X12" 4X54W) for 260$ shipped to my door. It included bulbs. (nice setup with good ballasts/lights)

If you do order make sure you call him. Great customer service from what I've heard.

EDIT*** check out the solar hoods he has.. I think that would look nice over a rimless...JMO

Well suspending the fixture wouldnt be a problem. I had planned to do that anyway.
its a 24inch deep tank and i was going to suspend it at LEAST a foot over....

What about a two bulb fixture?
Im trying to figure out if that will be around 60-100Micromols of PAR

At 36 inches from the substrate a 4 bulb T5HO fixture, with the bulbs close together, should give you about 60 micromols. Lower it to about 32 inches and you should get about 100 micromols. At those heights the spread of the light should give pretty uniform light at the substrate. I agree with mmelnick that a 24 inch long fixture should work fine, with less spillover of light.

So my options would be either a 24" 4 bulb hung about a foot above the tank
or a 36" 4 bulb hung about a foot above the tank...

I dont want shaddowing, or dark spots...


My concern is simply, is the 36" 4 bulb going to be too much?

and would the 24" fixture on this 36"Lx24"Wx18"H tank going to be enough spread?

Either fixture hanging a foot above the tank won't be too much light, and if it were too much, just raising it a bit more would reduce it. The 24 inch fixture should work fine, and eliminate a lot of light spillover.

Shawnts106 said:

So my options would be either a 24" 4 bulb hung about a foot above the tank
or a 36" 4 bulb hung about a foot above the tank...

I dont want shaddowing, or dark spots...


My concern is simply, is the 36" 4 bulb going to be too much?

and would the 24" fixture on this 36"Lx24"Wx18"H tank going to be enough spread?

Click to expand...

To be honest, I don't think that it would matter all that much which one you got. The 24" and the 36" would put about the same ammount of light at the bottom of the tank. I think the longer fixture mounted that high would just light the carpet next to the tank with the extra bulb length.

I have a 24" T5 fixture mounted about 5" above a 20 long (30" long tank) and get no shadows on the edges at all. So going higher with a slightly longer tank should be just fine.

Hmm...

Now to decide which one will just look more visibly appealing

Shawnts106 said:

Hmm...

Now to decide which one will just look more visibly appealing

Click to expand...

Is the carpet on the floor really beautiful? :biggrin: Sorry, I couldn't resist.

LMAO! well if you like 1970's retro orange... glazed carpet then yea.... IMO it looks like a combination of smashed(as I cant right pure'd because i have no idea how to type a french letter) carrots and baby $#*!... yep.