HighonPottery
Member
Get the biggest you can afford right now is what I'd say. I got mine for around $50 and its a 45L/min (~2 cfm). It's a decently strong pump but I don't think it is quite strong enough to create BIG siphoning action needed to suck down that vortex in 4gal liquid. Dunno if it's the shape of my bottle since its one of the newer ones with a handle cast into bottle (vs completely round) but I couldn't get it to vortex even though I have pretty much the same pump size as everyone else at 2CfM. Perhaps it just needs some tuning to get the right conditions?
Vortex is nice and all, and I'd assume it's superior system, but I think many would agree simply getting lots of DO into the brew via high CFM pumps + air lift/splashing in a "no-dead-spot" cone-bottom brewer is going to be more than sufficient to make a decent brew.
Edit: re-reading your question - I think you were asking about liquid flow pumps, not air pumps. If that's the case you want an air pump. Flow pumps will cut up all the good stuff you're trying to grow on the impeller blades. Air pumps will provide oxygen for the aerobic environment you're trying to create for the beneficials you want to multiply.
Vortex is nice and all, and I'd assume it's superior system, but I think many would agree simply getting lots of DO into the brew via high CFM pumps + air lift/splashing in a "no-dead-spot" cone-bottom brewer is going to be more than sufficient to make a decent brew.
Edit: re-reading your question - I think you were asking about liquid flow pumps, not air pumps. If that's the case you want an air pump. Flow pumps will cut up all the good stuff you're trying to grow on the impeller blades. Air pumps will provide oxygen for the aerobic environment you're trying to create for the beneficials you want to multiply.