I think it's fair to acknowledge that the above paper is NOT a peer reviewed article NOR does it even mention kelp products. Broad generalizations about fungus and different products and conditions, the article really is bunk. To extrapolate that in some conditions M fungus is not necessary due to native populations or that compost tea is hard to effectively study and then blanket those products as bunk altogether truly is short sighted.
The ONLY thing that keeps my DWC set up pathogen free is the addition of weekly compost tea. Others have had similar positive results. So instead of dumping h2o2 or chloramines into your water, you can accomplish the same thing by adding beneficial fungus. This has been proven to help dozens of RIU members using dwc and there is an excellent thread in it.
https://www.rollitup.org/dwc-bubbleponics/361430-dwc-root-slime-cure-aka-116.html
SO feel free to stop by and claim that we are all victims of snake oil products that are not valid.
Cash crop..lol. Uhh huh.