How many leds for a 180g LPS tank

[sabbath]

I'm starting a 180g 72" x 24" x 24" LPS system. I have 3 DIY Led fixtures on it now with 12 3watt crees in each. Is 36 Leds going to be enough for a LPS softie system?

[Pittsburgh]

RapidLED's formula for tanks without SPS is:
LEDs = (Length of tank in inches x Width of tank in inches)/22

Which is 78 in your case... You could probably get by with less but 36 sounds a bit low.

[Neogenocide]

36 LED's over a 180g....no way. I'm running 96 LED's and it's great for LPS on the sand and mid way up, SPS mid to high depending on the coral, and whether it falls in the hotter spots or not.

[juice79]

I have 128 bridgelux leds on my 180 with no SPS. 36 is definitely not enough. I would agree 96 would be around the minimum.

[Neogenocide]

I have 128 bridgelux leds on my 180 with no SPS. 36 is definitely not enough. I would agree 96 would be around the minimum.

96 would be minimum if you were using all bridgelux. However with the higher power Cree's, 96 is optimal for a full mixed reef in my opinion. I run mid 550ish par up high, and anywhere from 150 to 220 on the sand bed.

Please ignore the SPS on the sandbed there, I had just pulled it in from a friends tank and was slowly moving it up as it was badly browned out.

http://i267.photobucket.com/albums/ii308/Cichlid-Wolke/Droid/2013-03-27213149_zps67ffef58.jpg

[sabbath]

Ok wow I thought I might have been on the low side. But not one third of what I should have. I usually hear of people turning them down really low because there getting bleached with LEDs. So I thought with mine maxed it might be ok. But I see now that it is too low. I just ordered a 2 x lamps of 80w 60" T5 to bump it up more. What do you think? Is this now on the low end of a LPS light? Or do I need more LEDs as well?

[Neogenocide]

Now that your venturing into a hybrid setup, there are more variables. Are you using reflectors, the quality of the reflectors, etc etc. Not sure I can comment on your setup as I've not done this yet.

[sabbath]

Now that your venturing into a hybrid setup, there are more variables. Are you using reflectors, the quality of the reflectors, etc etc. Not sure I can comment on your setup as I've not done this yet.

Not sure what brand the reflectors are. They are from Reefgeek.com. Here is what they stat. " 96% German reflective aluminum"

[AMDphenomx4]

What LED series are you using and what are their bins?

[sabbath]

What LED series are you using and what are their bins?

Here is the Leds that I'm running with the main page info. Is this the Bin info?
Qty-6, I run at 700ma
CREE XP-E Blue 3W LED (Run at 700ma)
Min. luminous flux 39.8lm @ 350mA
1000mA max. drive current
465-485nm wavelength
CREE part number XPEBLU-L1-0000-00201

Qty- 18, I run at 700ma
CREE XT-E Royal Blue Led
Min. radiant flux 500mW @ 350mA
1500mA max. drive current
450-465nm wavelength
Forward voltage 2.85V (typical)-3.5V (maximum) @350mA
CREE part number XTEARY-00-0000-000000N01

Qty- 9, I run at 700ma
CREE XP-G R5 5W Cool White LED
Min lumens 139 @350mA
1500mA max drive current
5,000-8,300K color temperature
Pre-soldered onto star shaped pcb
CREE part number XPGWHT-L1-0000-00H51

Qty -3, I'm running with the Dim4 direct output at 500ma
CREE XP-G 5W Warm White LED
Min. lumens 114 @ 350mA
1500mA max. drive current
2,600-3,700K color temperature
Soldered onto star-shaped PCB
CREE part number XPGWHT-L1-0000-00EE7

[AMDphenomx4]

Can the drivers you are using be adjusted at all to get to above 1000mA?

[sabbath]

Can the drivers you are using be adjusted at all to get to above 1000mA?

The Cool whites and the Royal blues can be set up to 1300ma's. I have the Leds in 3 of the makersled designer heatsinks with fans. At this point I have not pluged in the fans. I pointed a heat gun at the top of the heat sink and see 105deg with them at 700ma. So I could have more cooling for them.

[AMDphenomx4]

While it may be able to keep LPS with what you have now, I would suggest doubling the number of white LEDs on the 1300mA driver. The LED setup you currently have has a bit under half the white that you should shoot for to keep things happy. There's also a lot less blue than other lights would use. Basically, I would at least double the number of white LEDs to have them equal in number to the royal blues. There should be enough light to keep the corals you want happy if you do that. More than 18 would be better though. Without more, SPS corals won't be an option unless they're really close to the light.

For reference, I'm using the Ai Sol as a proven baseline and using the output of the LEDs you've listed to compare. There is about 50% more royal blue, but 60% less white, and 70% less blue. The lack of blue shouldn't be a problem if you add more whites, preferably some neutral to add warmer spectrum. You should be able to do it for under 50 dollars and get it up to where it needs to be.

Also, the XT-E royal blue you listed has 550mW on the spec sheet, but you say it is 500mW. There's a big difference. What drivers are you using?