How they doing, i would purchase an airstone and pump, get a gang valve as well to let you be able to turn the flow up and down, if they are ok, i would add the med back that you have removed once you have put the airstone in the tank, so you removed 30% of the water, so work that out in gallons, then add the med to the gallons you have removed.
Also till you get the airstone i would turn the temp down abit, good luck.