Yeah, I wouldnt sweat it. Waiting a few days isnt much of a problem especially if your tank is over filtered if there is such a thing. For some reason i waited a month to do my "weekly" water change. With my tetra pf10 (90gph) and aquaclear 30 (150gph, but on low so more like 95gph) kept the tank water crystal clear on my 10g. But there was a lot of crap still in the gravel. And a missing fish.