Please help. I'm looking for a light with very little light spill

[pompeyjohn]

Hi all,

I have watched a load of videos of different lights, and it is hard to tell from YouTube clips. Your advice appreciated.

Here is where I am right now

• Tank is an IM Fusion 40 (display dimensions are 24" x 16" x 19")
• Tank is recovering from a Christmas crash (thanks tank sitter). It is pretty bare, but will likely be SPS dominant.
  
• Running 2 Hydra 26s 12" above the water line.
• Which is 55" up from the floor and so floods the living room with light.

It is distracting when you watch a movie and four flowing pucks are visible.

I thought about building a canopy to surround the lights. Then one of the lights died. I am taking that as a sign to get new lights.

So the requirements are even spread of light in the tank, with as little light spill into the room as possible. I know right?

• The Orphek Atlantic Compact looks like it would light the whole tank, but be overkill.
• A Radion G4 with diffuser might work.
• Two or three Chinese black boxes dialed down low, and set close to the water line.
• A non dimmable ati t5 fixture.
• The Maxpsect Razor with flaps.
• Something nanobox?

I looked at the aquatic life hybrid, but it is a little too wide. The rear bulbs would be over the sump area. Also my hunch is that if the hydra is close to the water line there is going to be spotlighting again. So I might as well so with straight t5.

Thanks for reading. Sorry for the ramble. I have been up late too many nights looking at lighting videos.

All advice and comments appreciated.

 

[mcarroll]

So the requirements are even spread of light in the tank, with as little light spill into the room as possible. I know right?

Not only possible, but easy with a little math. If you want, check out a blog post I made on it here where I explain an example: Online Triangle Calculator

Your current lights have 90º lenses if I'm not mistaken, and that particular angle makes for very easy math – at 90º your mounting height is equal to your coverage radius. (remember: 2•radius=diameter)

So at 12" from the water, your Primes are covering a 24" diameter – each.

Since your tank is only 24x16", that means quite a bit of light spill even from just one. With two you might be lighting the room just as much as the tank.

Drop each one to 8" from the water (16" diameter of coverage) and experiment from there with the horizontal positioning to get them blended right. You might even want them a little lower than that, but like I said start there.

Use a lux or PAR meter to make sure that overall light intensity doesn't change (much) when you make the switch. Use of a meter will also make blending the fixtures a lot easier.

If you really want to switch fixtures (try the above first!) then I'd suggest considering some strip-format lights such as an Orbit Marine IC Pro setup.

 

[mtraylor]

Yeah I would just drop the lights to about 7 to 8 inches off the water and barely tilt the lights away from your viewing area. That's it. Nice a simple.

 

[mtraylor]

Just FYI your PAR levels and spread will change dramatically so you may need to make some light adjustments. When you tilt the front a smidge lower, that will keep most the light out of your area and you will be happy.

 

[pompeyjohn]

Thanks all - the problem though is that at 8" the lights shoot a beam down the middle of the tank, whilst the sides are dark.

 

[pompeyjohn]

I'm leaning towards an array as opposed to a series of pucks.

 

[Finhead]

I'm leaning towards an array as opposed to a series of pucks.

Jsut my opinion but you could do something simple first to try, make a shroud and leave it at the 12". Here is what I mean, doesn't have to be 3D printed could just do it our of carboard for a quick test to see if it works. If it does then work on something permanent.
Ludnix's 50g Cube

 

[pompeyjohn]

Thanks finhead. That is a really good idea.