How much kelp extract per gallon?
like a gram a gallon more if you wish to fix a low "K" issue
I also will put in a shot of high % humate / humic acid like earth juice its kind of redundant with the EWC in there but I find if there is any toxicity among the micros and macros then doing so will increase the CEC of the biomass which tends to buffer it reducing the effects of the overload or deficiency by balancing the %CS K and the %CS H towards most optimum
for instance you want to add kelp extract to your mix because of its beneficial properties However your soil is good for "K" and Kelp extract is very high in K.
now the fix for high "K" is add gypsum or sulfur. which corrects by leaching out excess "K" However your soil is already high in both lime and sulfur and is above most optimum to high in pH. and the leaching process takes both time and excess water.
( say your neighbors lawn is above your garden and you get some run off and he miscorrects a perceived "N: deficiency with iron sulfide and more Nitrogen (although you know its " I " lock is a result of high pH water with loads of Alkaline salts and Cal in it. and he would be way better off sprinkling a combo of peat moss and cotton seed meal over it instead which lowers pH and increases "N" and to put a sediment filter on his irrigation system.) so you've built a corrective biomass barrier and planted fescue on it to reduce the "N" the "I" the "S" and lower pH of the run off.
But I regress
so you dont want to add either as a fix for the high "K" and the only reason you are adding Kelp ext is for its beneficial properties. so you do the only other fix you can and increase the CEC of the biomass in an effort to buffer the high Micros and Macros of "K" "S" and lime . now the lime and sulfur are doing a slow motion battle with each other over pH. and as we know too high a pH will cause neut lock out esp of iron and Mang and also "P" (when it gets over 7.5) so we want to increase the bio availability of these
a humate like earth juice is like mainlining the CEC of the soil it also goes through pumps way better than EWC and also converts quicker.