Did you get the T5 or T8 version? The T5 is worlds better, especially with a good reflector (another variable). Then the Arcadia tubes come in different strengths/intensities. These numbers refer to Arcadia T5 tubes in a Sunblaster Nanotech reflector, which is just very shiny and amplifies the strong light. The numbers separated by a / are what you’d measure with the 6.5 / 6.2 meters if you had one. At least the 6.5 is a great thing to buy if you keep reptiles that need UVB.
You’re aiming for Ferguson zone 2 with some of your forest tortoises and zone 3 for your desert/grassland species.
I got significantly higher numbers than that out of my Arcadia 12% HO tubes in reflectors in my enclosures, which illustrates again the need for each of us to use a meter in our own enclosures.
@Nrc470 here is the meter to get: https://www.solarmeter.com/model65.html
On the bright side (Very punny), buying this meter will actually save you a bunch of money in the long run. "They" say to replace your UV bulbs every 6 months to make sure they are still effective. I find, with the use of a meter that is actually measuring the UV output, my tubes keep on producing strong UV for 2-3 years. With the cost of these high quality bulbs, the savings will quickly add up and eclipse the price of the meter. In addition to that fun fact, having a meter will also ensure that your UV levels are correct and that your tortoise(s) is/(are) getting the correct amount of UV all the time. Much like using a thermometer to adjust temps, vs. guessing.
That’s a shame. They’re really nice fluorescent tubes in a good reflector. Can a larger light be installed in your AP cage? And how do you like your AP cage? I’m waiting for one to be manufactured having ordered about a month ago. Everyone seems to say they’re worth the wait.