Question about new hairless rats eyes and sneezing.

Question
I'm a first time rat owner and just bought a hairless rat from a pet store. I'm not sure of his exact age, however, I know the pet store gets them as babies and he was there for around 6 weeks. I also bought a furry dumbo (male# at the same time to keep him company. They get along very, very well.
My problem is that I've recently noticed that he is getting dark circles around his eyes that were not there when I bought him. It almost looks like bruising and seems to have switched from his right eye to his left. I know they secrete something from their eyes, but it looks more like it is his skin and not a secretion. He is also sneezing quite a bit, though I'm not sure if that is normal.
I have no idea what it could be. Could it be caused by his food or bedding?
I'll give you a little information on his diet, bedding, etc.
-He is not neutered and, as I mentioned, lives with another male rat a little bit younger than him who is also not neutered.
-I feed him a mixed rat food #I forget the name since I've put the food in tupperware and thrown the bag away# that contains various seeds, nuts, berries, pellets, and corn as well as fresh vegetables and fruit daily #no oranges). I also feed him small pieces of bread, Yogies, rice crispies, raisins, and banana chips as treats. They have chew blocks and VitaKraft Corn%26 Fruit sticks to chew on.
-He gets fresh bottled water daily that I add Oasis Vita-Drops to.
He eats and drinks well.
-I use Carefresh Ultra bedding which is unscented. They love to tear up tissues for bedding. I use "nesting confetti" for my ratties to play with, Sweet Dreams soft bedding, and I also cut strips off of an old pair of soft pajamas for both my rats to make a bed out of inside their igloo. I washed them beforehand with no detergent.
-I clean their cage with Green Works and rinse it really, really well.
-My boyfriend and I are very careful not to spray perfumes or anything in my room since I read that rats have sensitive respiratory systems.
-There are no drafts or very cold air in my room.
-He lives in a very large tri-level cage with one inch spaced bars and a solid bottom.
-I let them out and play with them for a combined 3-4 hours every day. The cage is in my bedroom so they are constantly around me, even if they are in the cage.
He's very sweet and affectionate. He loves to lay with me, fall asleep in my sweater pockets and hoods, and cuddle as well as run around and explore.
-When I first got them, I had to wait for the cage to come in the mail so they lived in an aquarium for a week.
Could anything I'm doing or have done made him sick? I'm very worried since we've become very attached to each other. Any advice would be helpful. I hope I've given you enough information for you to let me know if there's anything at all I'm doing wrong.

Thank you so much!

Note: I have also sent this question to Sandra Conti-Todd

Answer
Odds are, it probably isn't bruising, but instead staining - although it may not look like it's being secreted from the eyes, I'm willing to bet it actually is. This is amazingly common with hairless rats. They are prone to many more eye issues than furred rats due to their general lack of eye protection (eyelashes!). Have you tried taking a wet tissue and wiping his eyes clean to see if the shadowing goes with it? I know, easier said than done; he may not tolerate it.

If it's bruising, that would be because of swelling or something of similar nature putting pressure on the flesh around the eye socket. If it gets worse, noticably puffy, and he begins to porph (secrete red tears) like crazy, then you should take him to a pocket-pet/rat vet and have him checked out. Otherwise, I really wouldn't worry about it.

The sneezing could be something normal for him - some rats are just sneezier than others - and it may be a sign of something bigger. When you hold him up to your ear, do you hear rattling and/or monkey noises? Does his respiration/chest noise/lung noise sound clear, or congested? When he sneezes, is he sneezing fluid out, or is it dry? If he has a lot of fluid from his nose or has chest congestion noises, you should have him checked out. Otherwise, he's just sneezy.

Your care sounds wonderful - the only thing I feel important to note is that Vita-drops used in water should be changed out at least once, preferably twice a day. The vitamins will lose their potency throughout the day, and after about 8 to 10 hours are generally completely worthless. Beyond that, it's not overly necessary provided they're getting a good, healthy diet and you stay on top of their care.