We have a non-permanent dip tube from bargain fittings that we're using in our MLT. Despite everything we've tried, we're still pulling air through our pump lines after the water level goes below the bulkhead. We've tried w/wo teflon, snug/semi snug on the nut, swapping out washers, etc.
No matter what, we're still pulling pea sized air bubbles during the last bit of draw. We are able to completely drain the vessel without losing our prime (most of the time) - but we're a bit concerned that we 1) might be stressing the pump, and 2) will be introducing oxygen to the wort in the BK.
Wanted to see if anyone had any similar issues/remedies out there.