rostick555· Got Shrimp?
As mentioned about ph swings definitely not good, so as long as your ph stays constant at 7.2 that wouldn't be your biggest issue. The biggest issue I see is the temp being 75 at night. I have found in my experience that cardinals are the most sensitive to temps lower than 80. I keep mine at 82-84f also just straight tap and no c02. My ph is 7.5, tds 300 do to the higher temps, kh 11, and I don't use any water altering salts.