Miracle Grow with Moisture Control holds too much water

I noticed that the potting mix had settled and was no longer mounded at the top. Since the monsoons will be starting a couple of weeks, I thought now would be a good time to add some more potting mix. If the potting mix isn't mounded, then water can collect on top of the plastic mulch and effectively top water. This can cause too much of the fertilizer strip to dissolve and over fertilize. I have also noticed that the Big Boys have symptoms of Leaf Roll (not Leaf Curl) and the lower leaves are yellowing/browning. This isn't much of a problem with the Early Girls (same 18gal EarthTainer) or the Celebrities (5gal SWC). One possible cause is too little water or too much water, so while I had the boxes open I checked the moisture levels. The potting mix was more than moist or damp, but not wet. It was the same in all the 18 gallon SWCs and the buckets. I can't know for sure, but I blame the Moisture Control. I'm using 50% Miracle Grow Potting Mix with Moisture Control and 50% regular Miracle Grow Potting Mix. I have read other reports that the Moisture Control formula wicks and holds too much water for SWCs. I'll phase it out over time by mixing in more regular potting mix at the beginning of each season.