Sintered pneumatic muffler for bubbling?

[Julian]

Hmm, my air pump is a weedy little solenoid driven thing operating a diaphragm in conjunction with a couple of red valves.  Very low air flow, but in the tank it gets quite a circulation going and seems to do the job just fine if left over night.

With anything too vigorous I would imagine you run the risk of stirring up settled sediment, even if the bubbler is positioned well off the bottom of the tank.

[Jamesrl]

Try feeding air along the grain of a piece of white oak, it's surprisingly porous.

Drill and epoxy in a tube in to the end grain and pump air.

You only need it to be 20 - 25mm in section and approx 100mm long.

[Tony]

With anything too vigorous I would imagine you run the risk of stirring up settled sediment, even if the bubbler is positioned well off the bottom of the tank.

I'm of the opinion that stirring up the sediment is no bad thing, in fact I've taken to giving my bio a jolly good mix up every few days of settling and this seems (in a very unquantified, non-scientific way) to help with getting the fine soap to drop too.

[Head Womble]

In two days all the soap should have dropped anyway, so I can't see that this will help.

[willbuild]

with real ales they use soft spiels on the tops of barrels that are easy to blow through or hard splices whilst the ale is settling. would they be any good. think the soft ones are bamboo.

[Tony]

In two days all the soap should have dropped anyway, so I can't see that this will help.

I would argue that you need to quantify "all".  In two days most of the soap drops on most* batches, to give an OK 50:50 test.  But if you want to get down to 50ppm soaps (lovely crystal clear 50:50) then a little more can be required.

I would also throw in the argument about taking finished bio with you on longer journeys in drums, and finding red sediment at the bottom when you come to use them.  Why not agitate them up front?

*I say most, some batches are stubborn and hang onto suspended soap for a couple of weeks - agitation does seem to help with these too.