Understanding and managing suspended solids in intensive salmonid aquaculture: a review

Abstract

The intensive aquaculture of salmonids is a relatively young discipline within the animal husbandry sector. It differs to terrestrial livestock farming in one obvious and fundamental aspect – the aquatic environment. Besides great advantages such as buoyancy, the fluid medium also poses specific challenges for fish and fish farmers. One issue identified as a central problem in aquaculture is the presence of undissolved particulate matter in the water column. The ideal of fish living in pure, transparent water is seldom a reality as virtually every water body is subject to multiple inputs of solid matter, for example from the ground, the air and from the organisms living in it. In aquaculture, these solids are derived from both natural and anthropogenic sources, but by far the biggest input comprises excreted waste from the relatively high biomass of fish. The ratio of different inputs varies significantly between individual systems, dependent on factors such as the type of husbandry system, water exchange rate, the species being farmed, stocking density and the composition of the feed being supplied. This review aims to summarize potential sources of solid wastes in salmonid aquaculture, the properties of those solids and their implications for system stability, the quality of connected environments and the welfare of fish being reared. We will also review the expanding opportunities for solid management.

Selenium nanoparticles are required for the optimum growth behavior, antioxidative capacity, and liver wellbeing of Striped catfish (Pangasianodon hypophthalmus)

“…Under the current challenges of a high population, aquaculture presents a safe and healthy food source ( Dawood et al, 2021 ). However, sustainable production of aquatic organisms has to consider the intensive and super-intensive farming systems ( Schumann and Brinker, 2020 ). Indeed, intensive systems could afford high production yields from the lowest possible unit of water ( Van Doan et al, 2020 ).…”

Effects of suspended solids in the survival and haematological parameters of pacu juveniles ( Piaractus mesopotamicus ) in a biofloc technology culture system

“…Maintaining blood pH homeostasis is crucial for protein stability and enzyme function (Aboagye & Allen, 2018). In our study, the blood alkalosis found in treatments T500, T750 and T1000 on day 1 and T250 and T500 on day 5 was possibly related to TSS presence, which may hinder oxygen uptake in the fish (Schumann & Brinker, 2020). As the dissolved oxygen levels in the water remained similar between treatments, its direct effects on blood alkalosis were ruled out, leaving the hypothesis of possible functional hypoxia caused by TSS presence in the water, which would have interfered with the O 2 uptake.…”

“…Thus, such concentrations must be known for different fish species in aquaculture systems. The main effects of high TSS concentrations are skin irritations, fin erosion, blockage of the opercular cavity, gas diffusion inhibition, nitrogen compound excretion and changes in ion exchange (Holanda et al, 2020; Schumann & Brinker, 2020). In our study, the TSS concentrations that caused mortality in pacu juveniles were extremely high (6000 and 7000 mg L −1 ), which is rarely maintained in a culture system.…”

Improving Plant Health Through Nutrient Remineralization in Aquaponic Systems

“…Considering the 450 kg tons of fish in the system producing ca. Forty-five kilogram dry weight solids with a theoretical average P of 23.9 mg/g dry weight ( Schumann and Brinker, 2020 ), the solids treatment system encountered a theoretical P load of 1.08 kg. This resulted in ca.…”