If you notice any signs of stress or ill health in your fish, use the following information to guide you.
Moving fish from one location to another is one of the most stressful events in the life of a fish. You can minimise this with careful handling, but you can never really eliminate the risk of death. If the fish are not coping, they will generally start to show signs of stress within the first 2 weeks, so keep a close eye on them and be ready to respond. In most cases, fish tolerate moving and the introduction of new fish or plants, the cleaning out of the pond or the filter, but any of these events, however, can result in unhappy, sick fish. Signs of ill health are: not eating (in saying that, it is common for new fish in a new pond to be shy and skittish), isolating themselves, hanging on the bottom or top of the pond, and/or white film on the skin, tail or fins. If this is present in just one fish, you can afford to be patient and let nature take its course. If the bulk of the population is acting this way you need to act quickly.
For ornamental fish there are lots of quality fish treatments available. For aquaponics and fish you plan to eat, use of any of these chemicals is not recommended, therefore Pool salt is used to treat them. Here are some suggestions on salt treatment:
First test the water for Ammonia, Nitrates and Nitrites. If results show high levels of any of these you will need to do at least 1/3 to 1/2 water change (make sure you condition the water if it is from a tap). If the results are in the clear then you can treat the fish with salt. ( pool salt)
Add 3kg of pool salt to every 1,000 litres of water (e.g. for 500 litres use 1.5kg). Ensure that there is plenty of moving water and/or use an aerator. Reduce feeding to an absolute minimum. The fish should remain in salt until they are looking sociable and interested in food. You can test this by throwing tiny amounts of pellets in. When you think they are looking better, do 1/3 water changes over the next week or 2 to bring the water back to fresh, (remember, the salt will not evaporate). This salt level should not adversely affect vegetables in aquaponics.
If you don’t see improvement within 24 to 48 hours, and are still concerned about the fish health, turn off the water going to the vegetables and increase the salt to 5kg per 1,000 litres (an extra 2kg per 1,000 litres). They should remain in the salt for at least 1 week.
If you have any other questions please ask us.