Assessment of Crushed Water Hyacinth (Eichhornia crassipes) as Organic Buffer for Fish Production in Port Harcourt, Nigeria

Abstract

A preliminary study was conducted to evaluate and compare organic buffering capacity of crushed water hyacinth and calcium carbonate on acidic borehole water for aquaculture. Thirty, 25-litre shaded plastic tanks (20-litre filled with experimental water, pH 3.0) of three replicates per treatment of 180 g buffer agent were used. Treatments (T) were: control (C)[T1], wet whole plant (WWP)[T2], wet roots (WR)[T3], wet stem (WS)[T4], wet leaves (WL)[T5], dried whole plant (DWP)[T6], dried roots (DR)[T7], dried stem (DS)[T8], dried leaves (DL)[T9] and calcium carbonate (CA)[T10]. Temperature and pH were monitored once daily while dissolved oxygen, calcium and alkalinity were measured once a week for seventeen days using standard methods. Data were analyzed for analysis of variance and descriptive statistics using Microsoft Excel. pH values of T3 (6.7±0.22 ) and T6 (6.8±0.22 ) to T10 (7.2±0.22 ) on Day 17 were not significant (P>0.05) and within the range of 6.5-9.0 acceptable for fish production. DWP, DR, DS and DL competed favourably with buffering efficiency of CA. This study recommends use of at least 180 g of DWP, DR, DS and DL for treatment of 20 litres of acidic water for minimum of fourteen days for aquaculture. It is economical and safe for fish production and human consumption.

Key Words: Organic fish farming, organic buffer, potency, pH, water hyacinth