One quick-fix for a slow-drianing or under-aerated mix is to set the pot on top of a wadded-up towel, or on some absorbent fabric like cotton flannel that you let drape down below the level of the pot.
It has to touch the soil through holes int he pot, and the pot can;t have a layer of gravel or broken pots in the bottom "to encourage drainage".
When the mix touches the absorbent pad, a capillary link is formed that assures the cloth under the pot is exactly was wet as the soil in the bottom of the pot.
If the folded towel can absorb all the extra water form each watering, that works. It will use capillary attraction PLUS gravity to remove all perched water and open up as many air channels as the capillary film around every soil void or channel permits.
Or, if you let the fabric drape DOWN, it will let excess water drip away, or evaporate. This is also a great way to "de-salinate" a pot that retains too much water to be flushed without drowning roots.
It's analogous to this:
http://garden.org/ideas/view/R...
Al / Tapla feels that wicks like this aren't as good as a potting mix that just plains drains well enough! I have to agree. But "set the pot on top of a towel" is easier and faster than creating a different potting mix and then re-potting .