worth noting that there are two naturally high-mortality periods: first during the egg stage and then again when the trout first learn to feed. Some fish never learn to feed and simply starve. What is a normal death rate? Death rates are different from one stage to the next. With eyed eggs, a high survival rate is expected because they come from the hatchery tempered and treated against fungus. The loss of most of your eyed eggs suggests a problem. As the eggs hatch, and the fish age, survival rates improve. By the time fish are free swimming and have learned to eat, death should be an uncommon event. Losing many free swimming fish is, above all else, a sign that the tank environment is not healthy. As they grow, fish produce more waste, so cleaning and water changes may be needed more often. FISH My alevin are very active and are pushing fish into the corners of the basket. What does this behavior suggest? Should I be feeding them more? This is normal activity. At this stage, young trout prefer dark corners. Putting some opaque material over the breeder box may help to reduce the amount of light these fish are exposed to. UV light can be harmful to eggs and alevin. Fish at this age do not need any food. When at the end of the alevin stage the fish begin to feed, start with small amounts. See in Chapter 8 for guidelines on feeding the trout. Trout are being sucked into the filter. How can I prevent this? BioMax media bags or similar screening over the filter intake as recommended in Chapter 3. How sensitive are the fish to temperature changes? For best results, the tank water temperature for trout should be maintained as close as possible to 52° F. Fish can handle small fluctuations of one or two degrees, but sudden changes of almost any scale will be stressful. Rapid changes of 50 F or more are a serious threat to trout survival.
worth noting that there are two naturally high-mortality periods: first during the egg stage and then again when the trout first learn to feed. Some fish never learn to feed and simply starve. What is a normal death rate? Death rates are different from one stage to the next. With eyed eggs, a high survival rate is expected because they come from the hatchery tempered and treated against fungus. The loss of most of your eyed eggs suggests a problem. As the eggs hatch, and the fish age, survival rates improve. By the time fish are free swimming and have learned to eat, death should be an uncommon event. Losing many free swimming fish is, above all else, a sign that the tank environment is not healthy. As they grow, fish produce more waste, so cleaning and water changes may be needed more often. FISH My alevin are very active and are pushing fish into the corners of the basket. What does this behavior suggest? Should I be feeding them more? This is normal activity. At this stage, young trout prefer dark corners. Putting some opaque material over the breeder box may help to reduce the amount of light these fish are exposed to. UV light can be harmful to eggs and alevin. Fish at this age do not need any food. When at the end of the alevin stage the fish begin to feed, start with small amounts. See in Chapter 8 for guidelines on feeding the trout. Trout are being sucked into the filter. How can I prevent this? BioMax media bags or similar screening over the filter intake as recommended in Chapter 3. How sensitive are the fish to temperature changes? For best results, the tank water temperature for trout should be maintained as close as possible to 52° F. Fish can handle small fluctuations of one or two degrees, but sudden changes of almost any scale will be stressful. Rapid changes of 50 F or more are a serious threat to trout survival.
TIC-Manual-4th-Edition-FINAL.docx