250Watt + depth = enough?

[segraves1]

Are 250Watt MHs "bright" enough for a 31" depth tank?

I'm about to order a 44"L X 15"D X 31"H and want to make sure I will still have enough light penetration with 250Watt Iwasaki bulbs (plan to run a pair of these 250Watts over the tank). Do I need to/should I go up to a 400Watt?

[Reptoreef]

IMO, a depth of 24" with a more shallow height is far more reef adequate. On that tank, you'll need 2 with act supplimenting and 2 400's would probably be more efficient. 250's should be ok if using a DSB, though. I'm willing to bet that a 120 would be far more of a reasonable reef with the measurements you've given(48Lx24Hx24D).

[perpetual98]

Yeah, that's a goofy sized tank. Go with a 120G tank like Repto said. A little wider (good) a little deeper front to back (good) and a little shorter (better for 250W halides)

The problem with a 15" deep tank is that aquascaping becomes more difficult. I've got two 24" deep tanks and I love the space it affords me.

How much are you spending on that tank? I'm assuming it's acrylic (bad)

I just saw a 120G with dual overflows by me for $365.

[segraves1]

Yeah, that's a goofy sized tank. Go with a 120G tank like Repto said. A little wider (good) a little deeper front to back (good) and a little shorter (better for 250W halides)

The problem with a 15" deep tank is that aquascaping becomes more difficult. I've got two 24" deep tanks and I love the space it affords me.

How much are you spending on that tank? I'm assuming it's acrylic (bad)

I just saw a 120G with dual overflows by me for $365.


the shape is dictated by the piece of furniture we want to put it in.....

yeah we are planning acrylic for ease of working with......why wouldn't we want acrylic?

[davejnz]

Chris,Eric and J are making valid points about the odd footprint(surface area)of your tank.Your tank is 150gal with a 44"x15" footprint.That gives you 660 inches^2.For comparison,my 40 breeder has a footprint of 36"x18" giving me a total surface area of 648 inches^2.So i have 16.2 inches^2 per gal -vs- your 4.3 inches^2 per gal.
Surface area in a tank is crucial as it is where most of your gas exchange takes place.Besides gas exchange,A wide(18"+)tank has the benefits of allowing for a spacious aquascape.I feel with your 15" of width and 31" heigth/depth to overcome(build up your aquascape),it is going to be very difficult to build an open/spacious aquascape thats not relying on the sides of the glass/acrylic for support.A spacious open aquascape that's at least 3-4" off the sides/back of the tank is crucial in a reef tank.This allows the water current to flow behind and through the LR much easier than if you were to just start stacking LR aginst the back wal/sides of the tank.
Another point i would like to make is maintenance.I've always owned shallow tanks(18") so its pretty easy for me to reach down in there to do work on the tank.I recently drove to a guys house i met to trade some corals wth.The guy had a 300gal tank that was 34" deep.I had to sit there and watch him for an hr while he used his "rock clamp tool" to reach down in there and try to remove my corals then place his back in.ONE HOUR to remove 3 little frags and place 1 frag back in.After seeing that,I would never buy a tank deeper than 24",LOL.

[segraves1]

crud.....well....guess we will scrap the entire idea of using this funiture......

so how would a 48 X 24 X 25 work? pair of 400Watt, 6500Ks over it?

[Reptoreef]

250 watt 6500k's would be great for a depth of 25"

[segraves1]

250 watt 6500k's would be great for a depth of 25"

but would 400watts be too much (as I said, I have to order a pair of lights)?

[Reptoreef]

nope... it may be good for an eventual upgrade, too. You may have to acclimate corals more slowly to such an intense lighting, though.

[segraves1]

another idea I had was:

2, 250s
1, 400

to have the 2, 250s turn on in the morning (say 8AM) and run all day long (till 9PM)

then have the 400 turn on at around 11 and off at 3 to give a "strong light/noon time effect".....

anyone else do this or does it get anything?

[davejnz]

A single MH will illuminate a 2'x2' area.I think a pair of Mh's will be plenty.400's or 250's,either will work.I only run my 250 for 8hrs and let the actinics fill in the rest of the 12hr photoperiod.I think you'd be better off with just a pair of halides and pair of actinics rather than 3 MH's.250's are more than capable of providing good irradiance at 20'"depth.If your going to have a DSB thats 4"+,then 250's will be fine.However,I know Dakar uses the 400 sakis and loves them.They also produce quite a bit more PAR than 250's.