I agree w/those 2 observations. Maybe you already know this stuff, so disregard if so.....but Always shut OFF agitation when 200 or less gallons remaining. Some glyphosates foam up in the tank, some don't. Carry a small bottle of defoamer w/you & stop & check tank situation when it's about 1/2 empty. If you have foaming, add some defoamer to the tank. Next load you mix, add the defoamer at the mix. If when you stop you see no foaming, then save the defoamer & don't bother adding it to the batch either. Again, different brands of glyphos give different results.