How many lights and what wattage?

[mdrury]

Hi, I am setting up a 120 gallon corner Tenecor pentagon acrylic aquarium. The dimensions are 36" L x 36" wide x 36" high. I have a custom built stand and canopy with 13" clearance over the top of the tank. I want to be able to keep all types of corals and inverts, including sps and clams.

Now I am trying to decide how I would like to light the thing. I have considered using two 250-watt metal halide and two 96-watt power compact for a total of 692 watts, but I am wonder if that will supply enough light at the bottom of the tank. I have also considered using one 400-watt metal halide and four 55 watt power compact for a total of 620 watts. The second solution offers less watts per gallon, but may penetrate deeper.

Can anyone offer any advice and/or other solutions? Thanks!

[Reefland]

Are you sure the dimensions aren't 36x36x30 as shown on their website? If the tank is 30" tall, I would go with 2x250w as they will be enough to reach the bottom but if it's 36", I would go with 2x400w. The PC's are only needed to help provide some blue coloration for you and not the tank, they are not going to do alot in the way of providing usable light to your corals in comparison to the metal halides your adding.

[mdrury]

Nope, your right... The tank is 30" high, not 36". Thanks for the pointer. I just spoke with a guy at Greentree Pets in Clarksville and he recommended that I use VHO instead of PC as the bulb replacement cost are less and the bulbs last longer. Are you sure the atinic lights have no positive effect for the corals? I would think adding any supplemental lighting would be beneficial.

[Reefland]

I should rephrase that comment a bit. Adding the additional light is surely helpful, but when your main lighting is metal halides, the additional lighting from PC or VHO is purely supplemental; they are not going to add a whole lot to the scheme. Now if you went with 1 400w over the 36" long tank, using 36" VHO to cover the ends of the aquarium would be important, but you wouldn't want to use the ends of the tank for placing SPS or clams; only lower light requiring corals. So in that case, the additional light from supplemental lighting would be important and beneficial. If however you went with 2-250w or even 2-400w, the light spread from the MH is going to cover the entire tank and at that point, the additional output from PC's or VHO is just for your viewing pleasure really, as the MH are going o produce enough intensity to meet the requirements of any of your corals.

I had no idea you were located in Louisville, we're just in Bardstown.

[mdrury]

Hi Scott, I live in St. Matthews. Would be neat to meet you in person sometime as I am very impressed with the community you have created with reefland.com.

I just received an email from a person at Tenecor Aquarium Systems who recommends that I don't use Metal Halides over my tank at all. But he also states that he has no experience with sps corals or clams. He thinks that with 6 watts per gallon I am going to have fried fish for supper and perhaps a warped tank top.

I have a 13" high canopy over my tank and I still plan on using MHs. I think I may just go with 2-250 watt MHs and a few VHOs or PCs to immitate the dawn to dusk cycle for my viewing pleasure.

Thanks for your recommendations.

Murry

[Reefland]

Murry,

It would be great to meat sometime.

If the aquarium is manufactured with only small opening in the top for access, then yes, the metal halide bulbs can cause serious problems. However if the aquarium is built with proper euro bracing and cross bracing if needed, metal halides can be used fine. I'm not sure how they brace their tanks so I can't really comment on that but would say if they are overly built and MH is a problem, you should look at a different manufacturer.

The tank is the only problem here though, Metal Halide's are not going to cook fish or be too much light, no worries there. You do have to reduce heat from them and make sure to acclimate corals correctly to their intensity but they are THE way to go.

[mdrury]

The top of the tank only has two openings for access: one about 24" x 10" along the front and one 6" x 6" for the built-in overflow/pre-filter. I am considering cutting out more of the top, leaving a "brace" of acrylic across the top, to allow for better access and more light penetration.

I traded for the aquarium, so considering another manufacturer is not an available options at this time. I'm not worried about voiding warranties, but rather, getting the maximum out of my investment without needing to invest in a wet/dry shop vac (read: modding the tank with no leaks).

I really hope I can get this to work as I really like the size, shape and diversity this tank could offer.

Thanks,
Murry

[Reefland]

Oh ok, I thought you were going to be buying one new. I would consult another manufacturer before cutting any holes out, but it would seem that you could definitely do so. Are you familiar with Aquatica Reef in Bluegrass Industrial Park? He does a lot of Acrylic work and could definitely help you out with the bracing of the tank before you do any cutting. He could tell you what would be sufficient and what wouldn't.

[mdrury]

Yes, I know of him. I have visited his shop before; very impressive setup and nice selection of animals/inverts. Perhaps I will pay him a visit soon with photos and dimensions and see what he says. Thanks for all of your advise.

Murry