looks to me like a lot of people need to learn how to do proper PAR readings.. if I was getting that low out of a MH system I would throw it at the manufacture.
I did notice there were a lot of electronic ballasts, which have been showen to under drive bulbs so that would explain a lot of it. Also the reason I will not buy an electronic ballast. If I were to lay out the money for a new MH set up be dammed if I would settle for a second rate output to drive it.
but at last, T5 and MH are old school, LEDs are the way to go
for the numbers though
two 250watt SE AB10K's run by Magnetic M80 ballast, 8" above the water. just under the surface was about 1200, bottom of the tank ranged between 400 to 580 at a total distance of 28"
probably way more than I needed, if you have 250 on the sand bed you should be good for anything.
My new set up will be 36 LEDs and with 40 degree optics I should be able to hit 300 to 400 on the bottom of a 17" tall tank
Steve
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*everything said above is just my opinion, and may or may not reflect the views of this BBS, its Operators, and its Members. If cornered on any “opinion” I post I will totally deny having ever said this in a Court of Law…Unless I am the right one*
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