Guru Class Expert
Nov 25, 2005
While K+ has been discussed as a Mg2+ blocker in chloroplast, we should also consider relationship between leaf K+
and leaf magnesium because as K+ becomes more available, leaf magnesium concentrations for optimal growth increase. In general,
ratios of about 4:1 (K:Mg) or greater are often associated with the appearance of Mg deficiency symptoms. Satisfactory ratios of
Ca:Mg on an equivalent basis may range from 1:1 to 20:1, provided that adequate Mg is present.

This is from the December issue.... Just looking to try to clear some things up. Is that suggesting that there is evidence to suppoort high levels of K compared to Mg can cause a plants to not be able to ultize the Mg in the water colum, making deficiencies appear even though Mg is available in the water colum?

Just curious.... I am STILL having issues with my tanks that I am unable to answer or solve by adding *more* nutrients, that basically look similar to Mg deficiency...... im at a loss of what to do, its frustrating..... Just trying to find what the reason is that my plants wont grow healthy and lush....




Prolific Poster
Apr 1, 2005
Re: confused

How do you know it's a Mg problem? I add K to my tank, but in moderate amounts, about 10-20ppm total per week. I have no issues. I did however have issues using KCL, but not with K2SO4. The reason I began dosing K in the first place was because I was seeing deficiencies in my Hygro siamensis (pinholes), even though I dose KNO3 & KH2PO4. Since I started dosing K, no more pinholes. And I have liquid rock for water.

What plants are you seeing your problems in, or, what plants are you not seeing this condition in?