175W enough for SPS?

[BlueAbyss]

Alright I'm stuck. Again :lol:

Is a 175W MH gonna be enough to have SPS?

The tank is only a 20 tall, and I'd rather not have a more powerful light than I need, since I do plan on running them for 8 hours a day. But if I get the 30 tall which has the same dimensions but longer, I might want something more powerful... any thoughts would be helpful.

[BlueAbyss]

Hmm I should have put this into a different spot, it should probably have gone into the equipment forum.

[Snappy]

Yes you can grow most sps under 175 watt MH but many of them will need to be placed fairly high up to get good colour.

[Veng68]

Iwasaki 14K (sometimes called 15K) 175 watt MH with an electronic ballast has been tested to have the most PAR of the 175 watt bulbs.

Cheers,
Vic

[Aquattro]

I used 175w for the first year of SPS keeping. They'll live, and grow a bit, but not the same as you'd get with bigger bulbs. Especially if you go deeper, you'll want at least 250w.

[Veng68]

The 175 watt Iwasaki with an electronic ballast is supposed to have as much PAR as any 250 watt bulb according to Sanjay Joshi.

It's a pricey bulb though.

Cheers,
Vic

[fishytime]

If you do the 20" deep tank, you could go with HOT5s, 6+ bulbs would do nicely. Just thought Id give you a bit more to think about.:biggrin:

[BlueAbyss]

Well, the plan is to have 2 T5HO bulbs running 12 hours a day above the tank anyhow. This was more because of colour considerations more than anything, I want to use a 10K bulb because I like the really bright white sunlight effect. I was planning on using a XM 10K bulb with a PFO electronic ballast run 8 hours a day, and and 2 actinic or 50/50, maybe a Fiji Purple T5HO on for 12...

Does this change the equation at all?

OH, and the tank is like 15 inches deep, part of the tank will have a 3" sandbed (the seagrass part)....

[GreenSpottedPuffer]

http://reefcentral.com/forums/showthread.php?s=&threadid=1571128

[lobsterboy]

I used to be using 150wt MH, at a depth of 21in, and have switched to t5's. with the t5's at the same depth, i have experienced much more growth, and color in my SPS.

[BlueAbyss]

Hmm...

Well, the reason I'm going with MH to begin with is for the shimmer, I really like the effect and I think with the surge I will get some interesting caustics. The other option is to find a 70W MH to use as an accessory light, to provide that shimmer, and use 6 T5HO bulbs. Unfortunately, I've searched and searched for 70W MHs and they are impossible to find, so that idea is out... unless I call these guys http://www.venturelighting.com/NAindex.html. They have MH ballasts down to 50W, though I've never EVER seen a 50W MH bulb.

It all comes down to one thing... I need a wider tank :lol:

[BlueAbyss]

I used to be using 150wt MH, at a depth of 21in, and have switched to t5's. with the t5's at the same depth, i have experienced much more growth, and color in my SPS.

Hmm, a couple questions... what kind of bulbs were you using when you ran MH? How many T5s are you running now, at what wattage, with which bulbs?

[Rbacchiega]

I think if I remember he's running...okay I cant remember(I want to say 12 for some reason, but my brain is trying to recover from last night...) It's a big light unit though and the colour on his SPS are rediculous.

[JDigital]

I used to be using 150wt MH, at a depth of 21in, and have switched to t5's. with the t5's at the same depth, i have experienced much more growth, and color in my SPS.

That's not surprising... 150W is pretty weak for a 21" depth..

[BlueAbyss]

That's not surprising... 150W is pretty weak for a 21" depth..

How about 175 over 15" J? I guess what I'm asking here is will I get good growth and colour from 2 T5HOs (though they'll be 60/40 actinic and a Fiji Purple) and a 10K XM with a PFO electronic ballast?

At least, this is tentatively what I've decided I want...:lol: It'll probably all change, who knows maybe I'll go with all T5HO in the end... that's like 200 W of T5 over a 24" long tank, if I go with 8 bulbs and I end up using the 20 gallon after all, making it 25 W less than the proposed metal halide and fluorescent combo. I'm not sure if that translates to 25 W less light, or less power consumed though...

[JDigital]

How about 175 over 15" J? I guess what I'm asking here is will I get good growth and colour from 2 T5HOs (though they'll be 60/40 actinic and a Fiji Purple) and a 10K XM with a PFO electronic ballast?

At least, this is tentatively what I've decided I want...:lol: It'll probably all change, who knows maybe I'll go with all T5HO in the end... that's like 200 W of T5 over a 24" long tank, if I go with 8 bulbs and I end up using the 20 gallon after all, making it 25 W less than the proposed metal halide and fluorescent combo. I'm not sure if that translates to 25 W less light, or less power consumed though...


Are you sure its a 20G tall?? I thought a 20G regular was 24x12x16...

Anyways, I had a 175W MH over my 20G (regular) and I had great Monti growth, as well as good growth on digitata, birdsnest... never kept the tank long enough for acroporas...

I doubt you will fit 8 bulbs over a 20G... 8 bulbs generally spreads to 24x24.. You'd be hard pressed to fit a 6 bulb unit over it.. :)

[High tide]

Alright I'm stuck. Again :lol:

Is a 175W MH gonna be enough to have SPS?

The tank is only a 20 tall, and I'd rather not have a more powerful light than I need, since I do plan on running them for 8 hours a day. But if I get the 30 tall which has the same dimensions but longer, I might want something more powerful... any thoughts would be helpful.

Yes, a 175w MH will be ample on a 20 gal. aquarium. Your SPS will be fine at different levels of the aquarium. The Iwasaki was a good recommendation.:wink:

[BlueAbyss]

Indeed, upon further reading the Iwasaki bulb is very white when run with a good electronic ballast. So that's what I'm going with :biggrin:

[BlueAbyss]

Are you sure its a 20G tall?? I thought a 20G regular was 24x12x16...

Anyways, I had a 175W MH over my 20G (regular) and I had great Monti growth, as well as good growth on digitata, birdsnest... never kept the tank long enough for acroporas...

I doubt you will fit 8 bulbs over a 20G... 8 bulbs generally spreads to 24x24.. You'd be hard pressed to fit a 6 bulb unit over it.. :)

Yup you're right, each reflector for a T5 is about 2.5 inches wide, but I can totally fit a MH and 2 T5s over my tank. This would also work if I get that 30 gallon :wink: Though one end would be slightly darker.

On a side note, you're more than likely right about the way I labelled this tank... it probably is just a normal 20G, but most of the other 20s I've seen in the past (not many) were longer and only 12" deep.