Anyone own acrylic tank and have mh

[JARRETT SHARK]

I am gtting ready to start planing to upgrade to my 8' frag tank and wanted to go with 2-400w mh on one side and was unsure if it will melt the top or even reduce the lighting. The top of it is covered and only has med size opening on either side for acces into the tank.
Has anyone here used mh on acrylic?
The 8' frag tank is split to 2 seprate tanks so that 4' on each side so it has a brace in the middle. I was thinking of cutting the top more but unsure if it will not be that strong but guessing that the middle divider will make it like a top brace
i will post pics in a few

 

[albano]

About 10 yrs. ago, I had an 8' 300g acrylic tank, with 3 175w MH...the center bulb was about 6 inches over the center brace, and it definitely warped/ distorted the brace.

 

[JARRETT SHARK]

I had that feeling, i just dont want to go t5's

 

[Lenny718]

I had that feeling, i just dont want to go t5's

You could go with LED's but as you probably know it won't be cheap.

 

[ClosetFishGeek]

I have now had 4 250 wat mh roughly 9" from bulb to water surface....7 1/2 " to acrylic cross brace and I have not had any warpage.... It does get it toasty but no physical changes in the year that it has been in operation. My crossbraces are 3/4" in thickness. I also should mention that none of the braces fall directly under the center of the mh....

 

[JARRETT SHARK]

Thanks thane maybe i will just cut the top out as much as possible and give it a try

 

[ClosetFishGeek]

Thanks thane maybe i will just cut the top out as much as possible and give it a try

Anytime buddy...just be careful what you cut out....they were put there for a reason...Talk to one of the acylic guys to get an opinion.

 

[juiceguy]

If you are going to use 400w you can probably get away with keeping them up around 16" over the water line

 

[JARRETT SHARK]

Pics

You tell me if i can cut it out or leave it but unsure about if light will go thru the top

 

[SIReefer]

I know this is a shallow tank but I thought acrylic had to be fully supported on the bottom-not just around the edges? Would this lead to warping or cracking?

 

[JARRETT SHARK]

the bottom is supported right??

 

[MIKE NY]

I wouldn't cut anything. Two 400s directly over each opening on either side, that's what I'm doing on mine, and because it's such a shallow tank you can raise them further up, 10"-12" and be good....BTW nice tank!

 

[TRIGGERMAN]

I agree with Mike I think as long as you have the tops off and the lights over the open part it should not melt anything the openings are quite large.