My Betta refused to eat for 2 weeks! He would look at the food and near the end of the 2 weeks would occasionally eat/spit out the food. I tried the food that the LFS was feeding, he couldn't care less! I tried 5 different types of food then finally the little diva decided he liked the floating betta pellets.

Now my 2 cents (betta owner of a little over a month who has done a lot of reading/hand wringing/never heard of cycling before this, anyway...)I have read that the freeze dried foods can swell in the betta's stomach, so please be careful. I have also read that the pea works and the you can take a day off of feeding each week. The betta's stomach is the size of his eye...even though they greet you like they have never eaten before...

Again, newbie advice, but maybe he just needs a rest, if not I would try the pea. What were the water test results? Also, there are heaters that have thermostats in them to keep the temp constant...I've done plenty of hand wringing myself...

Good Luck and Get Well Soon to Susanna!!! (My betta is a crowntail too!)