SPS T5 PAR - What do you think?

[Hentz]

Hey guys, so SPS have been doing amazing in my tank with my new ATI 6x24. Getting great growth, decent color.

I finally got my hands on a par meter, come to realize, the top of my aquascape where a lot of my SPS are is only reaching about 180-190 PAR. So I went ahead and moved the fixture down (12" off the water) and am now getting 300 PAR in those areas.
Here's a PAR chart of my tank, what do you SPS freaks think of these PAR levels?

 

[gus6464]

If they were doing good already, why did you move it down so much? You are asking for trouble introducing 30% more PAR to your SPS like that in one swoop. Contrary to popular belief you don't need insane amounts of PAR for SPS. My SPS get 200 PAR tops and all have great color and are growing. While the growth is not lightning speed, I prefer for them to keep color over growing faster.

 

[SaltyWalter]

I have between 300 -375 PAR across most of my acros and 100-175 down lower where I keep montis, cyphastrea and zoas. I love all my colors and growth rate, but feel water quality and food also play just as important roles as PAR. Comes from 6 ati t5s (3 blue+ 1 coral+ 1purple+ 1 actinic)

 

[jdraider75]

I agree you may want to slowly lower that down. Increasing part that fast may make a few of them mad or even bleach or even colors get pale from getting blasted all of the sudden. Do it slow your numbers are fine. I run top of scape around 450-500. But only run daylights for 5 hours.

 

[shih87]

Here are my ATI Hybrid (LED 75w x 3 + T5 54 x 8) PAR readings....My ATI fixture is only 20~30 cm above water level and tank is 60 cm in depth. Later I found above water surface and below water surface readings may not mean too much, since LED direct hit or not make big difference on PAR reading on water surface.

02.16.2015

04.21.2015

My thread at http://www.reefcentral.com/forums/showthread.php?t=2470271&page=8. If you are interested, you can find more PAR readings from different tank directions there.

Note it seems better PAR reading above than yours, but my SPS grow is STOP!!! I think it is due to I am doing KH correction (from 11dKh to 7.5 dKh) now. I am just cross my figures they won't RTN or STN during this period of time ;-(

I agree above that since your corals show good grow, gradually change or no change maybe the best.

Cheers!!!

 

[Reefvet]

12" off the water

ATI's recommendation is 10" off the water so you can still drop it another couple of inches and increase PAR again. However I'd leave it right where it is for at least 3-4 weeks to let the corals adjust to the higher PAR and see if you like the change in colors.

I have digitata that's growing in 200 PAR and 600 PAR. They look the same in form, color is darker and richer on the lower light coral, but both look good. Growth rate is about the same in both levels of light.

I have a blue Mili in 200 par but it's color is dull. Fragged it and move that up to 600 PAR and it's very blue again and growing faster but thicker.

My point being that not all corals change dramatically in high par levels.

 

[sahin]

The new PAR value ie the ones in the posted photo look VERY decent. Having used T5's for many many years now, if you are hitting 200+ then that is good enough for most SPS and acros. Some like certain millipora require 350+ to pull all the colours, but 200+ is fine for most.

 

[ZON]

i keep my Hybrid PM 3" from surface and have around 700 PAR on whole tank