The volume figure for the Aqualifter is given as 0.22 liters / minute and the pressure as 30" (assumable, this is inches of water column). Most positive-pressure pump specs show a curve for volume plotted against head pressure (resistance). I should think that vacuum pumps would function in a similar fashion. I'm not sure if they're saying that it pumps .22 l/m @ 30" wc or if these are maximum figures for each, but I would guess the latter. I reckon a mite of experimentation is called for. Most of the Intermatic digital timers have a minimum interval of one minute, which would be a bit much (at .22 l) unless your tank evaporates as fast as mine seems to, but the actual flow rate may be substantially lower, which in this case might be a good thing.
Well, at least my algae is pearling...