I set up a CO2 system using yeast and sugar a few weeks back and to date
have noticed some pretty good growth in the plants.
N03 has consistently been 5 mg/l.
Over the weekend, I bought some liquid fertiliser called "Aquasonic Natural
Home Chelated Iron Formulation For Aquatic Plants" and added this to the
water after doing the weekly maint. and the usual 30% water change.
I checked the N03 yesterday and was surprised to see that it was in the
range of 20 mg/l.My immediate thoughts were that it was the fert. that was
to blame.
There is nothing on the label to indicate the breakdown of nutrients in the
product apart from a statement saying that it contains no phosphates, so I'm
not even certain that it is a true fertilser in the sense that it contains
the typical N P K ratio found in garden fertilisers.
Has anyone had any experience with the product and do you think the N03
spike is due to the addition of the fertiliser?

Thanks!