[CherryBrandy]

okey dokey , this is a slightly different approach....to what is quite a simple subject made very complicated !! We love these conversations on here so if you are caught in the cross hairs just ignore us all....try and forget about basking lights for a minute. Basking lights are purely for heat and serve only that purpose.

so in theory you would need A) a heat source to keep tort warm and B) a UV A AND B source for their wellbeing/shell/Vit D etc. This can be made up in different ways. ie bulbs for heat, tubes for UV's and combined bulb for heat and BOTH UV's.

so some basking lights have a combined UV A & B spectrum which is desirable because it combines heat and both the UV's ! bingo! no need for anything else because you have it all wrapped up into one bulb...BUT beware just the UVA bulbs .....are not combined.....and just UVB are not combined - you need both A & B ....sooo

Some bulbs come just in UV A and heat /without much heat like a household bulb, some just in UVB and with /without heat...what you have is a UVA basking (with heat) light for heat and UV A only and probably covers your UVA output not sure on % , and separate UVB. again not sure on % of UVB .Different reptiles have different requirements and a lot of reptile keepers (not torts) like UVA as it 'softens' down the light and makes their habitat all reptiley...and they eat better and have a bit of warmth to boot.

I think your set up is a little quirky as it has a UVB bulb and then separate UVA, both of which separately are not for tortoises but combined may just provide enough UV A & B - however what could happen is tortoise favours the heat bulb with the UVA and doesn't get the B spectrum.

Personally I would monitor and see what tort does and then when the UV A&B runs out in both (around a year ) then buy a combined one, or plead ignorance and swop them out for an arcadia D3 combined - *80W maybe, so if tort is sat under both bulbs he may l get UV A & B...honestly it sounds complicated but is like riding a bike...don't get me started on humans and UVC....love this subject...CB