Biobizz products and ph

Hi.
Im using soil and nutes from biobizz. Today my ph meter isnt working.
Looking in the net and i saw that if someone use biobizz soil and the water is 7.0 ph doesnt have to use ph down cause the soil gonna fix it.
Now when i use fish mix from biobizz i saw that ph is dropping down.
My question is does somebody knows how many point fish mix gonna lower the ph?

its true the soils fixes the Ph, but only to a certain level once saturated you're stuffed ...lol

like cooking, add a little each time as you can't reverse it

cheers