Ati sunpower output

[MichaelW]

I haven't worked with the 500, but if the meter is set up the same as the 200 make sure you have the setting on "Electric". Sun mode will give lower readings.

You aren't going to get the same par numbers as someone with 48" 54w bulbs. Make sure you're comparing apples to apples.

Coral+. Blue+ and AB special will give you the highest par numbers.

The fixture is probably too high as well.............move it down some so you have about 350 at mid level of your tank.

The 500 doesnt have option to choose between sun and electric.

I was under the impression with t5 the longer bulbs just cover more area to give light not necessarily give off more light right under the fixture?
I see comments like above where they have the fixture higher than mine (mine is 10 inches) with actinic bulbs that i dont have but getting 550 par.
It could be the meter and not the fixture. I also got lower than expected when testing under my leds.

 

[rhinonm]

So with the MQ-500 you have to multiply each reading by 1.32. The new meter does read led spectrums better but doesn't measure under water as well as the old 200.

google: Apogee Releases Calculator for Underwater PAR Measurement

 

[rtparty]

I was under the impression with t5 the longer bulbs just cover more area to give light not necessarily give off more light right under the fixture?

This is correct. Higher wattage (read longer) bulbs do NOT produce more PAR. At least not enough that it matters.

Here are some calculations:

24" = ~1w per inch
36" = ~1.08w per inch
48" = ~1.125w per inch
60" = ~1.33w per inch

The "extra" wattage is mostly wasted and not turned into usable light. The 60" bulbs do tend to have slightly higher PAR per inch but it is negligible for our use.

So while it isn't apples to apples to look at the PAR from a 48" ATI and wonder why a 36" doesn't have the same numbers, it is usually close enough for our purposes. What shouldn't be compared is two different brands of lights UNLESS you are comparing them against each other. For example, fixture A puts out 20% more PAR than fixture B when using the same wattage.

 

[CoralNutter]

I have a funny suspicion that is has to do with fan speed because the dimmable ATI has an auto configuring fan controller that keeps it running optimal speed. Have you tried tuning your fan?

Sent from my SM-G935W8 using Tapatalk

 

[Big E]

This is correct. Higher wattage (read longer) bulbs do NOT produce more PAR. At least not enough that it matters.

Here are some calculations:

24" = ~1w per inch
36" = ~1.08w per inch
48" = ~1.125w per inch
60" = ~1.33w per inch

The "extra" wattage is mostly wasted and not turned into usable light. The 60" bulbs do tend to have slightly higher PAR per inch but it is negligible for our use.

So while it isn't apples to apples to look at the PAR from a 48" ATI and wonder why a 36" doesn't have the same numbers, it is usually close enough for our purposes. What shouldn't be compared is two different brands of lights UNLESS you are comparing them against each other. For example, fixture A puts out 20% more PAR than fixture B when using the same wattage.

I stand corrected...........I just remember when I tested my friends tank with 24" bulbs he was pulling considerably less par than my 48" bulbs. It could very well have been other factors involved.

I would agree the other factors like ballasts, cooling, bulb types,ect. are important considerations.

 

[Piper27]

I have a funny suspicion that is has to do with fan speed because the dimmable ATI has an auto configuring fan controller that keeps it running optimal speed. Have you tried tuning your fan?

Sent from my SM-G935W8 using Tapatalk

How do you tune a fan on the dimable units?

 

[rtparty]

I stand corrected...........I just remember when I tested my friends tank with 24" bulbs he was pulling considerably less par than my 48" bulbs. It could very well have been other factors involved.

I would agree the other factors like ballasts, cooling, bulb types,ect. are important considerations.

Ballasts, cooling and reflectors play the biggest role in how much PAR a bulb will produce. Assuming the bulb(s) is a good bulb to begin with.

You could also take the same set of bulbs and put them in 5 different, but same brand, fixtures and you'll have differing numbers. But does it really matter if one fixture reads 300 and another is 310? I've always chalked that up to the acceptable range of error.

 

[rtparty]

How do you tune a fan on the dimable units?

In the controller you can set fan speed. I believe there are YouTube videos about it from ATI

 

[drawman]

Anecdotally my 24" x 4 bulb powermodule had way less PAR than I had expected when I was doing measurements over my frag tank while running 2 C+ B+ P+ bulbs. I run my fans on the slow side as they make a ton of noise when I ramp them up :/.

 

[MichaelW]

Im starting to think maybe it is actually the par meter.
I have a 2 bulb 80 watt hamilton fixture running 1 coral plus and 1 blue plus and about 8 inches under that (in air) was only like 300 or so if i remember correctly. So this also just doesnt seem enough... Granted they are not a "cooled" fixture bht it is in an open hood with fans creating airflow.

The other thing i am thinking (no idea if this could happen or not) it could be is possibly my house electrical is not providing the correct amout of power?

 

[Potatohead]

105 - 110 degrees of air temp leaving the fixture is pretty much bang on. FWIW I have the 24x8 as well and mine leaves at 108 on 9v setting, room temp is usually 69-70. I bet the meter is wrong.