Rate My Par

Johnson556 · Jun 11, 2018

My 180G is now a month old and I finally got my hands on a par meter. I’m not sure how to interpret these numbers, I know they’re high but too high for any of my current SPS? Most of them are in light between 380-430+ PAR. Flow is Generated by 4 MP40QD’s.

For my LPS I’m going to say absolutely, I’m guessing it’s a matter of weeks before my purple and green hammer turns translucent.

The readings where taken at the lights strongest point which lasts from 3-8pm, kessils at 90% and six 80W T5’s on. Kessils are at 45% at this time and my T5’s consist of 4 ATI B+, an actinic, and a coral plus, eventually will remove a B+ and add another C+.

Current SPS in Tank:
-Green Stag
-Miyagi Tort
-Pink Lemonade
-Strawberry Shortcake
-Strawberry Sorbet
-AussieHighlighter
-Bubble Gum Millie
-Rainbow Millie
-Sunset Millie
-JF Red Hot Setosa
-Green Tenius
-Greg Hiller Aqua Delight
-Greg Hiller Blueberry Acro
-Unknown Dark Green Acro with blue polyps
-Upscale Microladus
-Red Dragon
-Hawkins Echinata
-Red Planet
-Gatorade Birds Nest (to be sold)

Crabs McJones · Jun 11, 2018

Johnson556 said:
My 180G is now a month old and I finally got my hands on a par meter. I’m not sure how to interpret these numbers, I know they’re high but too high for any of my current SPS? Most of them are in light between 380-430+ PAR. Flow is Generated by 4 MP40QD’s.

For my LPS I’m going to say absolutely, I’m guessing it’s a matter of weeks before my purple and green hammer turns translucent.

The readings where taken at the lights strongest point which lasts from 3-8pm, kessils at 90% and six 80W T5’s on. Kessils are at 45% at this time and my T5’s consist of 4 ATI B+, an actinic, and a coral plus, eventually will remove a B+ and add another C+.

Current SPS in Tank:
-Green Stag
-Miyagi Tort
-Pink Lemonade
-Strawberry Shortcake
-Strawberry Sorbet
-AussieHighlighter
-Bubble Gum Millie
-Rainbow Millie
-Sunset Millie
-JF Red Hot Setosa
-Green Tenius
-Greg Hiller Aqua Delight
-Greg Hiller Blueberry Acro
-Unknown Dark Green Acro with blue polyps
-Upscale Microladus
-Red Dragon
-Hawkins Echinata
-Red Planet
-Gatorade Birds Nest (to be sold)

Not bad, a little high for my liking. I'd prefer it in the low 300's around the top of the rockwork and closer to 100 to 150 at the sandbed for your soft corals. But if acclimated properly your corals will accept these numbers

Brian W · Jun 11, 2018

To me it seems a tad high. on the sand bed, unless you are going for a high par on the sand. My par is usually around the 300-400 mark at the rocks and 100 or so on the sand.

I have learned over the years that you do not necessarily need really high numbers to grow sps. Some if not all will grow in the 100 range according to my experience.

Also you will find that the lower the par the slower your corals may grow but they will be colored up more. Vise versa, if you have corals in high par they tend to grow faster but lack as much color.

Just my opinion and only comparing it to my old tanks with T5's. Your tank may be totally different than mine!

Johnson556 · Jun 11, 2018

I ramped the kessils down 10%, going to Test a few spots later tonight to see how that affects things. When I read 350 at the sand I was shocked.

USMC 4 LIFE · Jun 11, 2018

What Kessil light are you using and how high off the water line is it?

cracker · Jun 11, 2018

Thanks ! Gives mae a good idea of par reading for my own tanks. My 75 is just about what crabs suggests.

Johnson556 · Jun 11, 2018

They’re Kessil A360w’s. All light are about 7” off the water line.

Daniel Waters · Jun 11, 2018

I think your numbers look fine. If you really want to get the best data, take par numbers from just your kessils at 100% and your T5s separately. The LED par should be fairly proportional, i.e. your par values at 50% intensity on the kessils should be close to half of what they are at 100% intensity (assuming you are not changing the color channel also, as that also can also impact the kessil par values). After you have that data, you can then gauge how much each (led / T5) is contributing to your combined par and you can design your lighting schedule exactly how you want it. My guess is your T5s are probably providing 2/3 of your lighting peak par values. You're going to have a hard time trying to create large differentials in par values (i.e. 300 par on top of your rock work and 100 par on the sand bed for instance), as the T5s are going to give you a pretty uniform distribution throughout the whole tank. If your LPS look okay, I wouldn't worry about it. If they look a little light stressed, turn your LED% down some, reduce your peak photo period duration, and / or try running 4 versus 6 bulbs of T5 most of the day.