UIUZMAR pH Meter for Water Hydroponics Supplies - pH Up and Down Tester Digital PPM Meter EC Meter Combo for Home Growers – Accurate pH Tester TDS EC Reader for Hydroponics

Im not a fan of a lot of bottles myself. I have a 2 bags for veg and 2 bloom. I do add skme stuff but not needed. For ph and ec I use this https://amzn.to/4uIIuCv Its $25. My last one lasted me over a year. I did have to calibrate it a few times. Generally just once or twice a grow. The solutions are easy and aren't too expensive. Its worked great. It does read ec as mc/us so ot will say like 4000 but the decimal always goes after the first number and then thats ec lol.