I don't stick my hands in my tanks at all. It's unnecessary. Why would you need to put your hand in the water? There's algae cleaners that have magnets on them, and ones with long sticks so you don't need to do that. And syphons (if you get the proper one) are long enough to reach the bottom of a tank without putting your hand in.
The only exceptions are the guys with really big tanks. Not 700 gallons, or whatever. The ones that are REALLY big.