Stock what the water can carry; buy healthy seed

A pond, tank, or cage has a carrying capacity set by oxygen, exchange, feed, and the people who can actually watch it. Ambition does not raise that ceiling. Overstocking shows up as slow growth, more disease, rising mortality, and worsening feed conversion — often before you admit the unit is too full.

Density

Match numbers to the weakest link: aeration that still works at dawn, water you can actually exchange, and labour on a harvest day. Understocking wastes space; overstocking wastes the whole batch. Review density when growth or water starts to slip, not only at stocking.

Fingerlings

Do not buy on price alone. Look for active swimming, even size, intact fins, and no wounds, swellings, or odd behaviour. Poor seed may never recover. Prefer a source other farmers in your climate already trust, with a paper trail you can write on the flock record the same day.

Acclimate to temperature and, where it applies, salinity. Investigate a jump in deaths right after stocking. Isolate or quarantine new lots when you can so one delivery does not infect the farm.

Use the fish flock as the stocking register.

In this series

• Water before feed — watch the pond first
• Stock what the water can carry; buy healthy seed
• Feed for conversion, not for leftover pellets
• Prevent disease with water, space, and calm handling
• Harvest gently, then ice without delay
• A batch without records is a business risk