When the lux is greater than full scale, it just reverts to showing a reading of 1. So, you were on the second scale, which means the readings all need to be multiplied by 10. But, that says this T8 light gives more PAR than the Hagen Glo light.

I notice that you can see two half images of a bulb on each side of both bulbs, so that is at least a fair reflector, while the Hagen Glo has a relatively poor reflector. Now I also wonder if the Hagen light also has an underpowered ballast. I think it is unlikely that your readings are wrong. But, readings with only one bulb will be very interesting too.

I knew something was wrong when I converted the lux to par and it didn't seem right .. I had forgotten about the scale being 10x.

Yes the reflector seems to decent. As the last photo shows on the right you can see 2 partial bulb images to the right of the bulb, then another image under the bulb and yet another to the left of the bulb.

Got some more readings for you. I added readings taken at the very end of the fixture on the right side. In my 1st post where the chain attaches to the fixture, I called it "right end" now it's called "right/chain. And "right end" is the very end of the fixture. Sorry for any potential confusion.

These were all done at night with the t8 fixture the only light on so these numbers may be more accurate but might be off from the previous readings. I got moving the fixture down pat so can breeze through fairly fast if you want readings taken in daylight again.

1st column is 2 bulbs lit. 2nd column is just 1 bulb lit .. front bulb. All readings used 2nd (10x) scale but in addition where I had to use 1st (1x) scale I gave that reading also. So in the column it will be 10x/1x.

**15" height**
Center, Center of bulbs--------555 -----371

Center, 9" toward back--------345------256

Center, 9" toward front--------298------151

Center, 12" toward front-------228 -----117

Right/Chain, Center -----------426 ------278

Right/chain, 9" back-----------264 ------196

Right/chain, 9" front-----------219 ------116

Right/chain, 12" front---------173 ------090/905

Right very end, center --------265------176

Right very end, 9" back-------172-------125

Right very end, 9" front ------148 ------075/756

Right very end, 12" front------118------060/601

**20" height**
Center, Center of bulbs -------401------258

Center, 9" toward back -------308------220

Center, 9" toward front--------253-----125

Center, 12" toward front-------208-----101

Right/chain, center-------------302-----193

Right/chain, 9" back------------233-----172

Right/Chain, 9" front-----------186-----094/965 (probably leaned toward sensor too much when switching scale)

Right/chain, 12" front----------155-----078/783

Right very end, center---------205------130

Right very end, 9" back--------162------117

Right very end, 9" front--------139------069/683

Right very end, 12" front-------116------056/556

**22" Height**
Center, Center of bulbs---------346-----220

Center, 9" toward back---------288-----202

Center, 9" toward front---------225-----113

Center, 12" toward front------- 191-----094/947

Right/chain, center--------------262-----165

Right/chain, 9" back------------ 218-----154

Right/Chain, 9" front------------171-----086/859

Right/chain, 12" front-----------141-----071/708

Right very end, center----------185-----117

Right very end, 9" back-------- 156-----111

Right very end, 9" front-------- 124-----063/635

Right very end, 12" front-------105-----053/530

**24" Height ** (to compare since I did it before)

Center, Center of bulbs-------- 307-----195

Center, 9" toward back-------- 260-----186

Center, 9" toward front-------- 212-----106

Center, 12" toward front-------182-----087/873

Right/chain, center-------------230-----148

Right/chain, 9" back------------196-----145

Right/Chain, 9" front-----------160-----081/816

Right/chain, 12" front----------137-----068/680

Right very end, center---------169-----108

Right very end, 9" back--------144-----105

Right very end, 9" front------- 120-----060/607

Right very end, 12" front------104-----051/512

**25" height **
Center, Center of bulbs--------295-----176

Center, 9" toward back--------254-----177

Center, 9" toward front--------207-----104

Center, 12" toward front-------179-----086/859

Right/chain, center-------------224-----131

Right/chain, 9" back-----------195-----136

Right/Chain, 9" front-------- --156-----078/786

Right/chain, 12" front----------135-----065/653

Right very end, center---------164-----096/959

Right very end, 9" back--------143-----102

Right very end, 9" front------- 117-----058/587

Right very end, 12" front------102-----049/495

**30' Height**
Center, Center of bulbs--------224----- 144

Center, 9" toward back--------195------140

Center, 9" toward front------- 177------097/972

Center, 12" toward front------155------080/804

Right/chain, center------------173------111

Right/chain, 9" back-----------151------110

Right/Chain, 9" front----------138-------075/751

Right/chain, 12" front---------121-------062/625

Right very end, center--------136-------087/875

Right very end, 9" back-------118------ 086/859

Right very end, 9" front-------108------ 059/590

Right very end, 12" front-----095/952--049/494

I was going to do a 2nd set of readings but it got late ... might do it Saturday night if you think it would help. Otherwise I'll move on to the other fixture I bought (the 10-1/2 brooder clamp-on). I'm going to have that Lux meter wore out and out of calibration pretty quick. :red_mouth

Thanks for all your help, Hoppy ... I really appreciate it.

EDIT: wish now I'd added the previous readings into this new post to be able to compare them easier. Maybe I'll come back later and do that.