hey bro heres some notes that could be very useful i had some Ph problems when using guano as a top dressing and that lead to a whole bunch of issues...
guanos should really be used in a tea, rather than being top dressed on btw.
Organics can be used with ro water 'stax', so long as the organics contain some micro source. The more common problem with organics is people mixing their poop soups and not allowing adequate time for the pH to come to a balance. It always needs to be aerated, bubbled or circulated for a good overnight or better to allow it's pH to settle, then pH it and bubble some more. Check it...then feed. Organics like earth juice for example are notorious for this need to stew it before use pH'ing situation.
A lot of folks just mix their poop soups, check the pH and dump it in the planters.
Where its unstable pH plummets without notice causing the lockouts.
This is another reason why guanos shouldn't be top dressed on, but rather stewed & bubbled into a nice tea form...
ph stability... Note that the minerals in tap water/nutes will buffer against a ph drop and it will take acid up to a point, then after the buffer effect (total alkalinity) has been overcome, the ph drops with very little acid. Tap water needs to sit at least an hour after adding acid before an accurate ph reading becomes available. If you don't use up the buffer and test right away, in an hour or so that ph will go right back up close to it's original ph.
hope this helps..