Compost, Ph in is 6.5 runoff is 5.0 is this normal

Just want to see if this is normal or if i might have some salt build up. Im using Fox Farm Ocean Forest.
Im in week 6 of flowering useing 3 part Adavaced nutes, with carboload overdrive. and enzymes. PPM is around 1100.
Any comments would be helpful

Around here my soil PH is always a little off so I throw in some lime before-hand as a neutralizer. Your water ph and soil ph are very different things.

ontarigrow said:

Around here my soil PH is always a little off so I throw in some lime before-hand as a neutralizer. Your water ph and soil ph are very different things.

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Thanks for the reply, So how would i go about checking the soil ph? i guess what im asking is, is there a way to tell what the soil ph is by checking the difference between the ph of the water going in and then the water coming out? Is there some kind of math formula to tell, or are there actual soil ph meters of some kind? Any help would be appreciated.