Ph Drops Massively When Adding Nutes

[jerkchicken]

 

[jerkchicken]

I switched them 2 weeks ago, they coming along nicely and didn't stretch much which I was surprised with because the night time temp was dropping slightly more than I wanted for last couple of weeks, I got a heater in there now tho. They seem happy tho, they're drinking and eating well and can't see any signs of deficiencies. Thanks again for the help people I'm back on track and they smell delicious already!!