Started using full array of Seachem fertilizers about 3/4 dose and my cardinal tetras started dying. They are wild caught. I don't think it was a coincidence. I keep a log and know when I started dosing and when the fish started dying. Has this happened to anyone else. My water parameters are 0,0,20,7.2ph. Has anyone had this problem with Thrive. Should I switch. What water percentage and time interval for water changes do each recommend. I do a 35 -40 % water change each week.