SO19Firearms said:The pH is an excellent call. Especially when you mix that in with the "plenty of CO2" call and it's resulting pH drop....*
The Iron call is always tricky - It's in a lot of books so I'm inclined to ignore it outright but it's dropping out is always valid with phosphates in the water - but then nobody (especially chemists) ever wonders about the phosphorous solubilising bacteria that try so hard to reverse that.....
As an aside - you can't presume your CO2 is fine because your DC is lime green - it's definately a start and the right place to be but we don't know that something needs 40ppm or 60ppm....or wether the flow's good etc (but that's not a slight - it sounds like you're def doing things right)
*somebody set up some controlled tests and we'll know.....
Thanks for the reassurance
I'm going to read up on iron suspension and see if there's anything I can do. Am sure something will turn up.
Interestingly, when you mention phosphates causing iron to drop out, I reduced my ei dosing by 1/3 to see how much my nitrates would drop (they are a pain at the moment, but that's another story that I'm working on). The result was pretty remarkable. They went from 60-ish by day three to only 25 after seven days (water change day). I've been having to do small water changes from day three of my week to keep them below 60. So with less ferts going in I noticed my Sao Paulo lost it's magenta colouring (at the moment I can only get the tips magenta). Does that mean the iron was being absorbed, and so not dropping? If so that seems to me that maybe I need to up my ei dosing of phosphates for my Sao Paulo, but maybe that is going to make matters worse for my ludwigia.
I'll stop there because I'm starting to confuse myself!!
There is much to do....
