slow stuck fermentation

[Imakewort]

lately I have been experiencing slow and or stuck fermentation's the only thing I changed I think is oxygenating with O2 for 1 min instead of 1.5 min. at a steady rate. how long do most brewers oxygenate for?

[DannyW]

Well you could switch back to 1.5 min and see if the problem goes away!

I've about given up on oxygenation. I went from aerating with a paint stirrer (a little propeller mounted in a drill) to 1min of O2 per 5 gallons and certainly didn't see any improvement - I even started seeing long increases in lag time and (I think, would have to check records to make sure) higher FGs.

I found some nasty growth inside my O2 stone about the time I got a pump. I went to pumping the wort into the bucket, pinching the hose to make it spray while it transfers. Now my fermentations are more consistent and FGs are pretty predictable.

They must be getting enough O2 for good growth - here (the big jug on the right) is what I saved from a propogator pack of 1056 to a 800ml starter to a 5 gallon batch of 1.040 blonde ale.

[Imakewort]

Might have to go back to 1.5 min of O2 but I remember getting better fermentation with my old aquarium pump, though I would like to get the same fermentation as my starters with them I need a blow off tube or yeast all over my stir plate