ADEP

The Aquaculture Development and Enhancement Programme, a reimbursable cost-sharing grant of up to R20 million of qualifying costs, administered by the dtic and claimed in arrears against qualifying spend.

Biological assets

Living fish held for sale, carried at cost as standing biomass on the balance sheet.

Contribution margin

Revenue less directly attributable variable cost, expressed as a percentage. 63.5% on a fingerling; 6.6% on a kilogram of grow-out fish.

Feed conversion ratio

Kilograms of feed consumed per kilogram of biomass gained. 1.52 by Year 5; published commentary suggests better than 1.4 is very difficult in South African practice.

Fingerling

A juvenile fish, here sexed male and approximately five grams, sold to other farms for stocking. The product on which 81.5% of Year 5 contribution depends.

Grace period

A period during which interest is paid but no capital is repaid. Three years here; on a two-year grace, cover in Year 3 is 0.62 times.

NEMBA

The National Environmental Management: Biodiversity Act, under which the use of Nile tilapia — an alien species in South Africa — is permitted only subject to conditions.

Nile tilapia

Oreochromis niloticus. Faster-growing and more feed-efficient than the indigenous alternative, but an alien species requiring a permit.

Mozambique tilapia

Oreochromis mossambicus. Indigenous and far less restricted, but slower-growing and less feed-efficient; the regulatory fallback, at roughly a quarter less tonnage.

Partial recirculation

A system reusing a proportion of its water rather than all of it, reducing pumping energy and capital relative to full RAS while retaining temperature and water quality control.

RAS

Recirculating aquaculture system. Energy-intensive and skill-intensive; published commentary notes the cost of rearing tilapia in local RAS can at times exceed the market price of the fish.

Sex reversal

Treatment producing all-male stock, preventing in-pond reproduction and the stunting that follows. Reliability of sexing is a principal quality attribute of the fingerling.