Ok I am sorry I do not know this brand and most of the MVB's do not emit enough UVB so I am guessing this is one good cause for the RI that is going on --- please get a Arcadia Pro T 5 w/ the 12% bulb UVB--- this is always recommended when people are using the MVB's -- to me they are a glorified basking bulb that does not take care of the UVB needs for the dragon - and are extremely costly -- good for heat but not so much UVB requirements - here is a website to get the UVB fixture -- https://www.reptiles.swelluk.com/arcadia-prot5-kit-desert-12 24 watt---Didn’t have the chance yet, will do today.
The dragon seem to be doing better since I replaced his UVB light and put up the temps, here’s the company I use :
If your going to stay w/ the MVB a better one that is recommended is the Mega Ray -- https://www.reptiles.swelluk.com/mega-ray-mercury-vapour-lamps depending the on the tank size they carry the 100 watt and the 160 watt - temps are what your looking for mainly you want to be able to keep your surface basking temps - ok so I read back on the post and you have changed to a long tube fixture for the UVB? Or jut the MVB your using?