Light Question

[jwildman]

Hi,

 

Have a 180 gal Tank (6'x2'x2') and am trying to figure out the best lighting. Want to be able to have and grow SPS. I am between 3 choices;

 

1. 2 @ 250W MH and 2 96W PC's or

2. 3 @ 250W MH and 2 96W PCs or

3. 2 @ 400W MH and 2 96W PC's

 

Any opinions or suggestions welcome.

 

Thanks,

 

John

[DEEPBLUE]

In my opinion you should go with 3-250MH and 2 PC so that you have full coverage. I have a 240gal with 3-400w MH and 2 140w VHO's and my tank is 6' long too and I have full coverage. Also you should go with 14k bulbs, I've had great success with growth in my tank.

 

Eric (Deepblue)

[xeon]

I would suggest three MH's not matter if you go with 250's or 400's. The rule of thumb is they cover a 2' square. Since you mentioned SPS right off the bat, I'd go for three 400's. The 250's would suffice IMO, but be marginal. I would also scrap the two PC's and use two 6' VHO's instead.

[Caribbean Jake]

I agree and support XEON on this one. You should go with 400's and VHO's.

Jake

[emissary]

I'm actually doing this right now. I opted for 3x250W + 2 96W CF. I had the CF bulbs and ballasts already...

[dbartco]

I have 3 400's and the put out a lot of heat and more expensive!! I guess go 400's if going with the lower PAR, higher K bulbs might be worth it though. If I had a 180 I think 3 250's 10K's would be fine, with VHO's instead of PC's. Have to change VHO's less often, and I feel give off less heat. DA's $.02.

[xeon]

Aside from me just not being partial to PC's at all... the VHO's will be 6' long and run the entire length of the tank. IMO, you get more light output and better actinic lighting (or supplemental light). Actinic PC's don't impress me much when compared to VHO's. I think PC's are fine for small tanks that need "compactness", but that's about it.

[flowerseller]

I use 3x250w -10Ks and 2x5' 140w- 03s on a 220H.

I see nice tanks as deep as mine with 175w

[jwildman]

Thanks all for the response, will def, switch to 6' VHO. Will also put in 3 MH's, but still on the fence about 250W or 400W. May be a decision based on the cost.

 

2 more questions;

 

1. any good suppliers for the lights (i.e. parts)?

2. Think the MH lights will be ok 12" off the water?

 

thanks again in advance.

 

John

 

 

I use 3x250w -10Ks and 2x5' 140w- 03s on a 220H.

I see nice tanks as deep as mine with 175w

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[dbartco]

12" should be fine.

Hellolights.com or championlighting.com are favorites.

 

setup costs are not too much different between the 400 and 250 (bulbs, ballasts etc..) . Operating costs per year are obviously more, and not to be overlooked.

[steveoutlaw]

Measure your canopy first. I have a 120g and I ordered the 48" VHO bulbs......well they don't fit in my canopy. 36" are on the way!

[fishface]

For a measured comparison, look up Sanjay Joshi's articles containing his analysis.

Here's the significant one: http://www.advancedaquarist.com/issues/feb2004/feature1.htm

It's an article on bulbs and ballasts comparing Photon Flux Density output for 250w bulbs. However he throws in 400W MH bulbs and there are some significant results.

I've pasted ONE section, please visit his site so that this is not taken out of context:

"Figure 9 shows the PPFD values for the unshielded 250W DE lamps as compared to the USHIO 400W lamp. It is very interesting to note that the PPFD values for the unshielded 250W DE lamp with the M80 ballast are about the same as that of the Ushio 400W on a standard ballast or a pulse start ballast, with much less power consumption.........however the Ushio 400W consumed 512W of power, where as the 250W AB lamp only consumed 304W of power. The difference in PPFD is 37 units where as the difference in power is 208W. Combine this with the fact that the reflectors for the 250W DE systems are much better given the smaller size of the lamp, I am starting to believe that the 250W DE 10000K lamps are a better option for most mid size tanks. The difference in intensity caused by the glass shield (about 18%) as shown earlier, can easily be offset by lowering the lights by an inch or two."

('Course I no longer know what is considered to be a mid-size tank.)

 

Whoa!

While I was looking for the article in Advanced Aquarist, and I got a hit directly to his website. I must have missed this 100 times! An Online bulb and ballast database referencing 630 spectral plots.

A Reeflighting Geeks Heaven!

 

http://www.reeflightinginfo.arvixe.com/

 

FF

[jwildman]

Thanks ... great article and links.

 

John

[fishface]

I've read a number of his articles including the one I quoted. But the bulb matrix is really great and somehow I never saw it before. I probably thought the website name was not current or something.

 

FF

[Guest Keyoke]

I've read a number of his articles including the one I quoted. But the bulb matrix is really great and somehow I never saw it before. I probably thought the website name was not current or something.

 

FF

34505[/snapback]

 

Yeah, I've seen this link a few times, but never actually clicked on it until a few weeks ago. I was impressed with the bulb/ballast matrix.

 

I'm still unclear on how a M80 balast can fire a SE bulb tho, since M80's from PFO are DE ballasts..

 

Someone ought to try and mirror that thing, just in case Sanjay ever decides to go offline for whatever reason. I'd hate to see that wonderful batch of information go away... wonder if we could host a copy of it?

[pez]

This may be a little late, but you might want to consider the DE MH lamps. I hear there are 400 watt versions now. If you go MH, you don't need the PC at all. I learned that the hard way. Personally, if I had a 180, I'd do 4 250 DE MH pendants - 2 10KK and 2 20KK.

 

If you're new to the hobby, I'd start with a smaller tank to learn the ropes and save $$ during the learning process.

 

-Tom

[steveoutlaw]

I disagree with Pez.......don't start small, go big. I had to spend too much on replacing things to go bigger. There is nothing like getting a tank and then finding out that you want more room. Then you have to buy new everything and only get about 1/4 of what you paid for the smaller stuff.

 

Also, on the lights. I think that using MH for actinic lighting is a waste of money. You can get 2 VHO's, the ballast to run them and all the wiring for about $100.00. that's a H-E-double hocky sticks of a lot cheaper than getting just 1 MH. Go for the 3 250w MH and 2 VHO actinics. I think you'll be happy with it.

[pez]

Let me clarify, by small, I mean 55-75 gallons or so. The step to 180 is a huge capital investment. Everyone makes mistakes or thinks of things they want to do differently for their (inevitable) next tank. Starting with a smaller "starter" tank to get your feet wet (so to speak) is a great way to make the inevitable mistakes without costing too much money. Once you get a handle on reefkeeping, jump up to the 180 and do it "right".

 

As for the actinics, we will have to agree to disagree. After nearly 10 years of reefkeeping, I've learned my lessons the hard way. Cost isn't the only factor in making decisions.