Grain bed not settling

I can't seem to find anyone having this problem via the search function so...

I mash in a 10 gallon Rubbermaid cooler with a false bottom. It worked great for the first 10 or so batches then recently the grains started not settling to the bottom. I get a lot of grains actually just floating on top of the water. This has lead to me having a lot less clear run off and a lot of little grain bits making there way into the boil. Then in the last 10min of the boil they all burst or something like that and my beer looks really gross. Luckily the beers have been able to settle out and still taste good but it has really been a head ache on brewday. I have changed my mill to not crush the grains as fine but that didn't seem to help I've also tried changing the run off speed. Not sure what else to try other than rice hulls which I would rather avoid purchasing. Anyone had this problem before or have any ideas to fix it?

never seen anything like this but sounds more like a problem with the grain verse your equipment. the only reason i could see for grain floating is that its not absorbing the water, either it has been coated in an oily substance not crushed fine enought etc. very intersting I would like to hear if someone else had a similiar problem.

couple thoughts.

are you stirring well enough when you dough in?

I don't think a vorlauf would solve the unsettling issue but might help with the little bits of grain you don't enjoy. do you vorlauf?

I was going to guess that a fine crush (too much flour) could be sticking the mash, but it sounds like you already troubleshot that. Maybe stupid question, but when you dough in, are you sure you mixing thoroughly enough? Could it be some doughballs in the mash that are rising during your mash?

Getting some grain in the boil sounds like it could be avoided by an extra vorlauf or two when sparging. If you are getting a nice rolling boil you also can skim off some of the initial hot break protein sludge which will bring those grain husks to the surface and that should help a bit too

Tinga said:

couple thoughts.

are you stirring well enough when you dough in?

I don't think a vorlauf would solve the unsettling issue but might help with the little bits of grain you don't enjoy. do you vorlauf?

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beat me to it Tinga

Tinga said:

couple thoughts.

are you stirring well enough when you dough in?

I don't think a vorlauf would solve the unsettling issue but might help with the little bits of grain you don't enjoy. do you vorlauf?

Click to expand...

dcHokie said:

beat me to it Tinga

Click to expand...

skipped over this becasue it seemed like the obvious question.

The brewpub I briefly worked at, the grain bed wouldn't really "settle" when we used UK grains for some reason.

We'd vorlauf at a pretty high speed/flow, and things would settle down.

MC

I stir throughout my mash and my beers end up clear. It seems to me that you aren't vorlaufing enough and thats why you're still getting grains in the BK. Also, make sure the False bottom is stuck to the bottom, sometimes it'll lift up and cause a big mess.

Thanks for all the responses. Yes I vorlauf, I used to only have to run it back through once or twice and then it would be crystal clear, now I do it 20 times and I still get stuff coming through. I also scoop out any hot break at 15min into the boil (I do a 75min boil) and then at the end it still looks bad. I also stir the grains well when I dough in. Also recently double checked to make sure the false bottom fit tightly. I'm kinda at a loss, hoping it was maybe just a bad batch of grain, it was a 55#bag of briess 2-row for the bulk of it.