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.