I don't know how anything would get in there. I am more concerned that some of the material itself is degrading somehow, although the unit is less than a year old.
I don't recall whether there is a white liner inside the unit. The casing is black plastic. The spiral tubing that the water runs through, which encircles the UV
bulb, is made of some sort of plastic or pvc
or polymer, and it is basically clear...it would also be worrisome if that is somehow breaking down. The maker says that the space age material they use for that is one of the features that distinguishes their product in terms of durability, in addition to the design, which has the water spiralling twice, I think, so that the exposure to the UV
What you say makes sense.
I sent an e-mail to Custom Sealife, the maker...waiting to hear back.