If you stop to think about it for a little bit an aquarium pump and a skimmer are contradictory; one is intended to keep the coolant agitated and oxygenated the other wants it to settle and be still for the tramp moil to separate.
I have found with the machine in my prototype shop that in cool weather, probably frigid from your perspective, the coolant is perfectly happy just sitting there. In the summer when we can get high seventies and low eighties it will go off when it stands for three or four weeks.
I think you will need to experiment; aquarium pump only for several months and see what happens; skimmer only for several months and see what happens.
Regarding rust I think you will find you need to go to a higher concentration than the coolant manufacturer recommends to prevent rust. There has been several threads on coolants, this topic did arise and that seemed to be the concensus.
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An open mind is a virtue...so long as all the common sense has not leaked out. |