Supplementing aquaponics with black soldier fly (Hermetia illucens) larvae frass tea: Effects on the production and composition of sweetpotato slips and sweet banana peppers

Productivity and Elemental/Chlorophyll Composition of Collard Greens in an Aquaponic System at Different Combinations of Media and Black Soldier Fly (Hermetia illucens) Larvae Frass Supplementations

“…Tere were six identical aquaponic systems located under a greenhouse that was previously described [5]. Briefy, a 1000 L fsh culture tank (175 cm deep, 160 cm wide × 43.1 height cm; polyethylene) emptied into a sump where water was then pumped (1 hp) into two separate plant culture beds that were identical in size/ volume (78.7 cm length × 116.8 cm width × 40.6 cm height; 280 L capacity; polyethylene).…”

“…After about a month, the frass was dried in a forced air oven (Despatch; LBB Series 2-12-3) at 100 °C for two days and then ground into a fne powder with a hammer mill. Te nutritional composition of the frass was measured at the Fayetteville Agricultural Diagnostic Laboratory at the University of Arkansas with inductively coupled plasma (ICP) analysis, and results were presented in Romano et al [5]. Te proximate composition of the BSFL frass was measured according to standard AOAC [19] methods and is presented in Table 1.…”

“…Terefore, it is common for aquaponic farmers to supplement with additional nutrients, and the most common include iron (Fe, in chelated form) as well as potassium (K) and calcium (Ca) that are often in the form of the bufers CaCO 3 and K 2 CO 3 , respectively [4]. While Fe, K, and Ca are often limiting nutrients in aquaponic systems [5], this may depend on the system type and composition of aquafeeds as well as fsh and plant species. For example, Yang and Kim [4] found that magnesium (Mg) and Ca were limiting nutrients during the aquaponic culture of tomatoes and herbs, and these defciencies were linked to "chlorosis."…”

“…In particular, several studies report that using black soldier fy (Hermetia illucens) larvae (BSFL) frass as a soil amendment produced similar plant growth [9][10][11] or even better compared to those receiving synthetic fertilizers [12,13]. In an aquaponics context, BSFL frass tea had no efect on either sweet banana chili pepper (Capsicum annuum) or sweetpotato (Ipomea batatas) slip production but did increase manganese and sugar, respectively, as well as consistently elevated water calcium, potassium, and phosphorus levels [5].…”

“…While foating rafts and media-flled beds are some of the most common types, media is sometimes avoided due to the higher cost and concern that the accumulated debris will subsequently encourage anoxic zones and undesirable bacterial growth/ toxins [3,14]. However, there is increasing evidence indicating that leafy greens grow faster in media, as observed in lettuce (Lactuca sativa) [15], mint (Mentha arvensis) [18], spearmint (Mentha spicata) [17], lemongrass (Cymbopogon citratus), spring onion (Allium fstulosum) [18], and sweetpotato slips [5]. Research into this is still new, particularly for aquaponic plants grown in cooler waters.…”