Mine was no doubt the heat and genetics, the Mandarin Cookies came out perfect as far as bag appeal goes.  Both of them have a great smell and could end up my best grow so far, certainly my best RDWC grow. 

Two things I did differently that may have helped is I let the plants sit dry until the wilted a little, that was less than an hour in veg and 6 hours at the last res change in flower. Then when I did each res change I ran the system with just the root nutes/supplement's for a day or two before adding the feed nutes.  I did a hard core schwazzing on both plants too. The Mandarin Cookies loved it, not sure about the Rainbow Kush because I had not grown it before. 

Another thing I learned is to pick a strain I like and grow it over and over again until I get it dialed in "perfectly".