Center brace shadow problem

[jdbassin]

My tank is a 56 column measuring 30 x 18 x 24 high, it has a plastic center brace about 2 inches wide that casts a nasty shadowline in the middle of the tank, currently the reflector is just a standard polished aluminum, I've been reading about luminarc 3's and spider reflectors. though the luminarcs seem like they'd solve the problem from what i've seen of them they are 8+ inches tall and I need it to fit under my hood, the spiders look nice but i need something to reflect light back under the centerbrace, they have no reflection on the ends just the sides, Anyone elso have a solution for the centerbrace problen that doesn't involve removing it which I;m not willing to do.:mad2:

 

[chadfarmer]

new tank

if metal halide is being use you will always have a shadowline

 

[Letmegrow]

I know you said you did not want to remove it, but, have you ever thought of taking the center brace out and then replacing it with a clear acrylic piece ?

That little flimsy plastic strip can be replaced.

Cut the center brace and leave yourself like 3" or so inches of the plastic brace making little tabs.
Then get a drill and drill two holes on each of the tabs, and then drill two corresponding holes in the clear acrylic strip and just bolt them together with a nylon screws and nuts.

I would go with the Luminarc III minis 14.5" x 14.5" x 8.5"
I bought two from www.thereefstop.com. Without a good reflector you are wasting your light.

 

[jdbassin]

the mh sits right over the brace so it cast a dark 2" shadow straight down the middle of the tank, a reflector that is angled not only on the sides but on the ends also, mathmatically speaking, should reflect light throuh this shadow line thus solving the problem. just wanna know what reflector others used for a simular problem.


jd

 

[jdbassin]

thx, Letmegrow, i was thinking of possibly doing something like that with acrylic, maybe i will, but as you pointed out i still need a better reflector anyway. the one i'm using now came with the ballast and socket. planned on upgrading anyway

 

[Letmegrow]

LA III, they are worth every penny.

 

[chadfarmer]

<a href=showthread.php?s=&postid=7601584#post7601584 target=_blank>Originally posted</a> by Letmegrow
I know you said you did not want to remove it, but, have you ever thought of taking the center brace out and then replacing it with a clear acrylic piece ?
Without a good reflector you are wasting your light.

you will still have a shadow, anyway you look at it --a little salt creep--water drops and also be careful that you dont melt it

 

[chadfarmer]

or just add another metal halide on both sides of the brace and probelm solved

 

[hagfish]

If you don't find a reflector just slap some aluminum foil on the end of yours. It should help a little.

 

[Goalie66]

<a href=showthread.php?s=&postid=7601658#post7601658 target=_blank>Originally posted</a> by Letmegrow
LA III, they are worth every penny.

I totally agree with this! I had a 200 oceanic with a center brace and used one of them in the middle and 2 normal parabolics on the sides and you could hardly see the shadow.


Tom

 

[dela]

Why don't you have two lamps? That is what I have over my tank since it has a black center brace. 30x18 is plenty of space to mount two fixtures.

Seems a bit more logical than replacing the brace!

If you place the fixtures correctly, there is no shadow at all.

Actually I've been using this arrangement to try and simulate sunrise/sunset. First one light comes on, then the other light comes on, then the first light goes off, then the second light goes off. So the direction of the light actually changes during the day. It's not always just "Noon" with some omnidirectional sun above the tank. - Who knows, maybe it's just a waste of time, but I like the idea, plus it extends the lamp life by not running them quite as long.