I have an Apogee 510... pretty good PAR meter for a hobbyist. I used to borrow a LiCor, but I moved and that got hard.
My tanks range from 300-600 PAR with some areas slightly lower and some maybe a touch higher. Since MH and T5 have light outside of the visible range (PAR meter only detects visible light), you are getting more light with T5 and MH with the same number as with LED... so 300 PAR from LED is not as much actual light as from MH or T5 at 300 PAR... the amount of difference depends on the light, of course. I offer complete light from UV to IR (350-850nm) so the low range energy and also Emerson Effect works in my tanks, if you believe in these things (I do).
I don't have much recent experience with LED over acropora, so I should not be offering opinions on how to run them. Most of my experience is with number of units, electricity, etc. when I spec'd out maybe switching and decided not to. My last foray with LED over acropora was when Gen 4 Radion just came out... so a long time ago and with different units.
therman uses Photon v2 and has perhaps the best acropora that I have ever seen under LED. He runs all channels at/near 100% and uses plenty of PAR. He did a video with ReefBum if you want to check it out or he has threads on here. He does not need trick or blue-only lighting, black backgrounds or photo boxes to show how awesome his corals look. He would be the person that I look to if I was using v2s.
You don't have to shoot for too specific of numbers with your residual building block levels. Set up a system and see where it settles out. My sandbed keeps no3 about .1 and my fuge, multiple skimmers and stuff keeps po4 about 1-3 ppb, but sometimes it goes up to 10 if I have a skimmer pump go out or fuge is too full and needs pruned. If you settle out at .5 and 7-9, then that works... or 1 and 6-12, then that works too. You get the point... set up a system and don't chase. If you need more export, then get something new to export more. BTW - these are natural, not low. Low is when you drive them below this with media or chemicals - this is a bad idea unless you really have an acute plan like Zeovit.
Lastly, my corals likely get more N and P than tanks with residual levels of 100 nitrate and 1.0 phosphate. They are available in forms that the corals can actually use, not on the back end with a test kit. I have a massive amount of fish and they get fed a lot. I also export a lot. Whomever came up with the BS about lower that with this light or higher this with that light likely has no idea what they are talking about since they probably only considered what they could test for, which is fools gold. Fish waste is what drives the bus for your corals. What most of them don't get is that even if they have higher N and P and their corals are doing fine then they are both 1). probably still getting their nitrogen and phosphate from fish waste and not nitrate and the one kind of po4 on the test kit and 2). that the higher levels of N and P are likely inhibiting calcification and
zoox production in some way, even if small.
