PAR readings from new light

[Matt Dean]

So bought an ATI Powermodule Hybrid. Took PAR readings today and wanted opinions on if it's too much or spot on.

4-T5s and all LEDs (running at 70%) are at peak for 4.5 to 5 hours. LEDs ramp up from 12:30 to 2:30 then ramp down from 10:00 to 12:00

PAR readings at peak are : 650 to 690 at the top middle. 350 to 400 mid tank and 250 to 300 at the bottom and side edges of the tank.

Al my frags/corals look super happy and colorful, but dont want to overdo it.

So...thoughts? Too much? Not enough? Longer or shorter peak period?

Cheers

 

[2_zoa]

You bought a new light and took par readings.

What was the par readings before you changed out your light?

 

[Matt Dean]

I never took readings before. I had an 8-bulb Tek Elite T5 fixture. I only use 4 T5s in combination with the LEDs which are 3-75W clusters.

I just restarted the tank so all the corals are new. So they wouldn't notice the difference but want to make sure I'm not overdoing it and frying corals.

 

[oldhead]

Well I guess it depends on what the corals are. Sps may be happy with those par numbers. Lps and softies not so much.

 

[RobZilla04]

If you are seeing good color and growth I wouldn't suggest pushing the intensity much higher.

 

[Matt Dean]

Thanks. I didn't want it brighter or higher. If anything I might dial down the LEDs a bit to be safe. I haven't seen any adverse effects yet but the light has only been up for a week.

 

[Matt Dean]

So weird!

So weird!

My PAR readings make no sense to me. I am getting as much or more PAR on the sand in 3 spots than I do near the top! Attached is a pic to show the readings I am getting. The meter is reliable.

I understand you will lose PAR in between clusters, but how can the bottom be hotter than the mid or top?

Is it possible the LEDs are too narrow a beam? can't figure it out.

 

[2_zoa]

Makes some sense to me. The LED's are crossing paths. You don't loose light, it just gets dispersed as the cone of light gets wider. The different clusters of LED's are crossing at the bottom and the light is "œadding up" if you will.

 

[Matt Dean]

Interesting thought. Could very well be! Thanks

 

[Matt Dean]

I am going to try just running 8 T5s during the peak hours to get the most spread and just use the LEDs for nighttime viewing. I rarely watch the tank with full lighting and I had good success with the T5s in the past.

 

[Matt Dean]

OK. It looks like the outside 4 T5s were bouncing off the glass and creating hotspots. When I used the inside 4 T5s instead, the PAR readings were 'normal'. Lower on the bottom and higher on the top. I gotta say, this ATI light puts out a LOT of light. Way more than the TEK Elite fixture did.

So, good to know the LEDs on the ATi are solid. Cheers