Ok,first of all.I apologize for giving out misinformation.I took a reading about 30 min ago.The tds floating between 270 and 280...That sounds about right.So when I checked the ph it was 5.5 as normal,then I decided to leave the meter in the solution for about 45 seconds,35 more seconds than usual.I normally let it sit in the solution for about 10 seconds...That's where I was wrong!as the ph sat at 5.5 after about 20 seconds it starting dropping all the way down to 4.7,Could this had been my problem?I had to think quick so I went into the bathroom and I got about 64 oz of water (out of the tap today...390!)I added it in my res,right now I am sure that my ph is at 5.7 and the ppm in the res is 290.I didn't add cal-mag nor food.