I use vinegar, and/or straight ammonia. The ammonia doesn't d much for the deposits left behind by the water I splash so vinegar is needed for them. Ammonia is great for fingerprints, and pretty much anything but the lime deposits. I do use windex on occasion, what I do is quite simple, I get my paper towel and walk away from the tank. spray the windex on the towel and then walk back to the tank and clean the glass. I don't use it on my glass tops, and I don't spray it around or on the tank. I've never had a problem, as long as I'm careful.
Dave