I will try the alcohol. Just alcohol then lots of water through?
Water first, alcohol after. The water will stay in the tubes and take a long time to dry out, but alcohol dries much faster so there won't me moisture stuck in the tubes forever. Obviously do not use the tubes until the alcohol has completely evaporated.
But, fwiw, a little condensation is NBD. Just run the pump with no parts attached until it dries. Sterilize every so often or replace if you see growth in the tubes, but condensation that dries quickly does not warrant concern.