Bioshelters's founder and president is John Reid, who as a college student spent the summer of 1983 interning with Hopkins. Today Hopkins continues to serve as a frequent advisor. No used water is flushed down a sewer or into a river, where it can set off algae blooms and suffocate fish. This ammonium is consumed by naturally occurring benign bacteria, which leave behind a nitrite solution. Then another set of bacteria attacks the nitrites, creating nitrates.
Nitrates are the prize, because they are absorbable by plant roots.
In fact, as any gardener knows, nitrogen is a key plant food listed on commercially sold fertilizers. Bioshelters even makes use of the fish feces, which can pose a problem for aquafarms because they eventually build up and may harbor pathogens that make the fish sick. Reid culls out the waste and pumps it to a nearby marsh. After several months of bacterial action the waste turns to sludge and is then spray irrigated onto adjacent vegetable fields, where a farmer raises more than 10 varieties of specialty crops, mostly high-value vegetables. No pesticides are used in the Bioshelters greenhouse.