I use an aquarium pump and diffusion stone with room air. I start aeration in carboy at same time I drain wort through my chiller plate into the carboy. Never had problem with clogged stone. I aerate for 30 min with good results, Fermentap recomends 30-120min with 45 min as norm for normal gravity beers.
Chris White has some recommendations from his book, Yeast: The Practical Guide to Beer Fermentation (p77-80). 8-10 ppm dissolved oxygen is proper amount. Higher gravity wort could use more disolved oxygen, not because of high gravity, but because of increased yeast pitching rates. He also mentions that a homebrewer can not get more than 8ppm with an aquarium pump and stone, even with extended times. Per White, only way to get 10ppm is with addition of oxygen. To reach 8-10ppm, you need to inject oxgen for one minute.
For higher gravity beers, > 1.092, must use pure oxygen and is recommended to use a second dose of oxygen at 12-18 hours to help with attenuation and help with decreasing diacetyl and acetaldehyde.
Nice info to have in the back of your mind , but 30 min with aquarium pump is just fine for normal gravity beers for me.