Backyard Aquaponics
A place to discuss aquaponics

Pull out a older plant and inspect its root ball, you will find worm egg sacks in there, i find heaps, feel bad sometimes pulling plants out

? what pathogens are you actually referring to?
Say who?
Any link to study or research?

this is what I've fund out, and here is the link to the full book in case you whish to add some real info to your knowledge bank...
http://www.sciencedirect.com/science/ar ... 7407002273

Worm-bed leachate.

Eight beds (1.5 m by 6.6 m and 1 m deep) were used to obtain worm-bed leachate. Each bed was covered with a plastic sheet to protect the vermicompost against sun and rain. A total bed area of 79 m2 was available. Cow manure was composted thermophilically for two months while mechanically being turned over every 15 days. The composted cow manure, adjusted to 80% moisture content, was placed in the beds to a depth of 0.5 m and earthworms (Eisenia fetida) were added at a rate of 25 g earthworms/kg cow manure or 2.5 kg earthworms m-2 bed. The mixture was left to vermicompost for two months.

Each bed contained a leachate drainage and collection system. Leachate from each bed was collected in a separate 200 l tank, pumped into a central collection 1500 l tank and characterized.

Characteristics of the worm-bed leachate.

The worm-bed leachate was analyzed for total and faecal coliforms (Escherichia coli), Salmonella sp. and Shigella spp. (USEPA, 1999). Salmonella and Shigella were determined by serial dilution.
A sub-sample of 10 ml worm-bed leachate was added to 90 ml 1% peptone solution under sterile conditions and 10-1, 10-2 and 10-3 dilutions were made with sterile 0.8% NaCl solution.
A 100 µl aliquot was plated on two selective media Salmonella-Shigella agar and sulphite-bismuth agar. The second medium is highly specific for Salmonella.
The colonies were identified by form and colour (USEPA, 1999). For the measurement of total and faecal coliforms (E. coli), a 100 µl aliquot of each serial dilution was incubated in lactose broth for at 35ºC for 24 hrs and total coliforms were counted. The faecal coliforms were differentiated from the rest of the coliforms by incubating a 100 µl aliquot of each serial dilution in E. coli medium at 44ºC. Gas production in each assay was considered as positive after 48 hrs. Results were confirmed by plating on eosin methylene blue (EMB) agar, incubating for 24 hrs, and examining for typical coliform colonies (USEPA, 1999).

The worm-bed leachate (mean of three samples collected every 8 weeks) had pH 7.8 ± 0.1, electrolytic conductivity 2.6 ± 0.2 dS/m, 128.3 ± 42.2 mg suspended solids/l; 46 ± 12 mg Na+/l, no detectable NH4+, 834 ± 71 mg K+/l, 59 ± 9 mg Mg2+/l, 84 ± 13 mg Ca2+/l, 130 ± 2 mg Cl-/l, 247 ± 43 mg NO3-/l, 168 ± 11 mg PO43-/l, 47 ± 13 mg SO42-/l.
The fulvic acid concentration was 1.5% and the humic acid 2.4% of the total C content of the worm-bed leachate. As such, the humic to fulvic acid ratio was 1.6.
The electrolytic conductivity of the vermicomposting leachate was low indicating low concentrations of dissolved salts while it contained large amounts of K+, NO3- and PO43-. Considering the above mentioned characteristics, the vermicomposting leachate could easily be used as a fertilizer.

The germination index for tomato was 55 ± 5%. A germination index > 50% indicates that the worm-bed leachate is mature (Alvarez and Grigera, 2005). The worm-bed leachate was free of pathogens, i.e.coliforms (Escherichia coli), Salmonella sp. and Shigella spp.
The reduction of pathogens in the worm-bed leachate could be due at physical and biological factors during vermicomposting (Li et al. 2008).

Sounds like a common denominator