Can you give a description of what they are "clinging" to the glass with, such as some sort of uniform gel, and also the general size of them. If there is no gel, they seem to be independent of each other, and are the size of fleas, then I would say pods, but I'm just throwing it out until I know more about them.
They are spiral feather dusters. They are very common and cannot hurt anything. I have alot of them. The first time I saw one I thought nothing of it then the next week there were about a dozen, then they were all over my tank. They are harmless though. All you have to do is just scrape them off after you think there are too many of them. If you look really close to them you will see the tiny hairs comming out of the end. They are kinda cool if you keep watching them the just keep growing in circles become a bigger and bigger spiral, but they dont get any bigger than a millimeter though.
Ok, do they look like anything else besides white dots when they grow?(kinda ugly just sitting on my glass)
How(what) causes them to grow? Will I get lots now? Are they healthy for the tank? Will my fish eat them I scrapped some off glass and the fish didnt eat those.
I have seen my angel pick a few of them off my glass. Their maximum size is only about 1-2 milimeters. Calcium is what helps them grow healthier. The only way they would be good for the tank is just cause they most likely filter feed. I usually just scrape the ones off my front glass and leave the ones on the back and sides. When they grow they just look like spiral tubes that are very small. My guess is that they will reproduce and you will get lots more. Couldnt tell you for sure though.