30 psi for 3 days sounds like way too much carbonation. I used to do force carbonation but now I prime my kegs and get better results. But when I did the force carbonation I started at 5 psi and worked my way up to say 20 psi, increasing the pressure every couple of hours. I used a carbonation stone as well and never left it on the gas for more than a day. Now I simply add 5/8 cup of light malt extract dissolved in one cup of water that has been brought to a boil to the keg before siphoning the beer in and then seal it up and forget it for about a week and a half to two weeks. Hardly any sediment and the carbonation is spot on. I would recommend this method to anyone but if you want to do force carbonation you simply have to make sure not to overcarbonate. There is a carbonation table in the book "Brewing Quality Beers" by Byron Burch. An old book but a lot of useful info in it and it can be had for a few bucks on Ebay. Best of luck. Force carbonation is a bit tricky until you get it down.
I have a pro brewer friend that force carbonates using the method you described. It works well for him. My problem is that I would forget to go down and change the pressure every day. In addition, my wife would not want to wait that long for here IPA to be ready!
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