MH Coverage

[spikehs]

I am lookin into setting up and having some troubles on deciding what kind of tank/light combo to go for. I have decided that I want to keep it as simple as possible with minimal lights. So I am tentatively going to go w/ the aquariumlight.com Single 400w mh canopy.

For the tank I am lookin at doing a cube style 30"w x 30"l x 20" h. I know MH are supposed to only be able to cover a 24" square area, but since this is a 400w and it will only be 20" deep i figure I could stretch that a bit by raising it up. I was planning on having a coral island in the middle and nothing on the outter edges so it doesn't need to be full intensity there. My only hesitation is i just dont want it to look too dim on the edges.. Thoughts?

Oh yah, one more quick question. What would be a good turnover for a fuge/sump 5x tank volume? I want it to be quite, so the slower the better...

[Delphinus]

Hi Sean,

Personally, I think you'll be OK with the setup you're describing. I think you can probably raise the pendent somewhat if you find the light to be uneven. With a 400W lamp over a tank of that depth, you'd have some wiggle room.

As a comparison, I am currently running a 30x30x30 cube with a single 250W (DE) pendent and I find it's just right (I have the coral island in the middle idea too). If you like, come by sometime and check it out. It's not a technical SPS tank so it's suiting my needs perfectly. In fact I don't really notice the edges being dim at all (they probably are, but it's not perceptible to my eye. I have lower light LPS in this zone so it works out fine.) So that's why I think a 400W pendent would give you all the flexibility you need.

The only thing I miss is the dusk/dawn effect and I'd like to one day see about putting something extra on for that. Maybe some t5's or something. But for now the setup is working fine.

Also, I try to aim for no more than about 5-7x sump turnover myself. I think that's enough to be able to keep your heater in the sump without having to worry about the main tank losing too much heat. Going faster just increases the gurgle noise and also increases the chance for microbubbles to persist. I hate microbubbles and I've had very poor success designing baffles and sump setups that eliminate microbubbles and I think it's in part that I tend to overdo the sump/tank volume turnover. As far as that is concerned, I think minimalist is better than overdone (IMHO).

HTH

[spikehs]

Tony,

What pendant are you using? The one from aquariumlight.com is going to cost me about $375 to my door (w/ shipping and gst). 250w DE is supposed to have a similar output (PAR wise) as a 400w SE correct? Except it uses less watts? Or am i incorrect? Thanks for the help!

[Delphinus]

Hi Sean, I'm using the Hamilton pendent with 14k lamp.

That PAR thing seems debatable... It probably has more to do with lamp selection and reflector design. I would think two bulbs of the same spectrum side by side without reflectors, that the higher wattage one would "win". But I like the compactness of the DE pendent very much.

If you wanted to get really whiz-bang technical, a 400W lamp with a Pacific Garden Supply Lumenarc III (or Lumenarc A3 mini) reflector would blow away the competition. But they are not the prettiest reflectors, you'd probably want to have a canopy just to sort of keep the overall presentation of the tank nice.
http://www.pacificgardensupply.com/products.asp?cat=2

There was talk a while ago about a group order for these reflectors. If you're not in a hurry to get something set up you might want to investigate this route too.

The only thing is that these are very large reflectors and probably require a little creativity and DIY skills to get mounted.

I liked the idea of a pendent because it was plug and play. All I needed was something to hang it off, so I made a hangman style thing and it's worked out well. Simplicity has its pluses as well. I wasn't sure whether to go 250W or 400W. But in the end what decided it for me is that I hope to make this cube tank a second tank, so I wanted to keep its electrical costs somewhat down. I.e., if I'm going to run 400W's then I want the 400W's to go over the SPS tank. This tank in question is just my species setup for my ritteri plus maybe a bunch of softies and other LPS that wouldn't fit well in a high flow SPS setup (if and when it ever gets done).