@Smorf Alright here you go this is still gonna be hard with these pictures.
Alright the first one is just straight water, the left side being just after dropping in the drops and the right after it was shaken up, being that the base ph liquid is yellow once you drop it in you can notice it start to change color so long as the ph is higher than 6.0 which is the lowest for this scale, but in this case in person i would of put the ph at 6.8-7.0 instead of the 7.2 it looks like in the photo.
Now here is some dirty water which is some of my organic coco mix with a bit more EWC mixed in just to make the water a lot dirtier for this example, now this is where it gets tricky taking the far right as an example "shooken up" one would say that the ph is a 6.0 or under due to its color, but looking at the center picture you way notice the water right near the top has a slight green tint to it and not the yellow of the ph liquid by itself or what a 6.0 or under would look like, so because i watched the drops go in and noticed that slight green hue, to me i would put this in the 6.4ish and under range as up close when the drop are put in they give off that color with a tad more yellow, which when you consider the base liquid is yellow then that is indicating that the ph is higher than the base 6.0, at first its hard to tell but after you do quite a few its actually pretty easy to get it in the rough ballpark of around 0.2ph or so, and i have backed that up when i had a meter kicking around.
Now if your water is dirtier than this, just go get a decent meter as this isn't gonna work, but on average my water isn't this dirty and there are a few tricks to getting this method to work, say for example your measuring run off, i put enough water that i know the ph of through a pot so that its just starting to run out a little bit clear which is only about 10% run off or so then i leave it there and come back in 20mins-hr, and then put in just enough water into the pot for it to start dripping again, typically i don't have to add any and can just squeeze the pot, but i catch those couple drops and use them for my test, so because i let the water sit slightly and i know what went in it pretty easy to figure out if things are out of wack if your testing for that, which usually if it's the case you flushing anyways and will be checking as you go along till things are balanced.
The other trick is just collect your sample water in another container and let it sit for awhile as any heavy particulates typically will drop out over time causing your water to be clearer in the long run, that and or run it through a coffee filter.
So if your water is clear it works great but when its dirty its not as easy a decent ph pen, but to me its just as quick and gets me in that 0.2ph ball park pretty quick, once you can tell.
