I think your just talking about dust and such gathering on the top of the water? Yes it gathers very quickly.
I had glass tops that kept alot fo the dust off the water, but some still got in becuase of the air openings in the glass.
I got tired to changing my 5 gallons every week and a month ago went up to a 2 10G with filtration and its been a much more enjoyable experience and the my Bettas love the extra room and current.
It took a day or two for them to get used to the small current becuase they were used to still water. But the exercise of keeping up was good was them. The current doesnt bother them at all anymore. Infact the opposite now.
You hear about how Bettas live well in small tanks, but theyre noticeably more active, look brighter and healthier in the 10G
A catfish is also in each tank.