| Egg and Fry Development The majority of fish produce eggs, these eggs can take anywhere from 24 hours to five days to hatch, depending on the species and temperature. 
'Eyed up' Photo by: Tom Hammond. Once the eggs have hatched there follows a larval stage during which time the fry are helpless, they retain a large portion of yolk sac which they absorb over time. No food should be fed until the yolk sac has been used up, adding food at this stage will pollute the tank. At the end of this period the fry become free swimming. 
Newly swimming Ram fry. Photo by: Andy Many newly free swimming fry die of starvation, and probably as many from the pollution caused by over feeding. Suitable food must be on hand before needed, and water quality should be monitored daily. 
Photo by: Andy It is essential to maintain good aquarium hygiene, fry lack the fully developed immune system of their parents, and are sensitive to tiny fluctuations in water chemistry and temperature. Small daily or twice daily partial water changes need to be carried out, fry do not tolerate poor water quality well. 
3 week old Ram fry. Photo by: Andy It is essential to provide adequate space for the young fish to grow. Some fish are able to produce growth-retardant pheromones in order to limit size relative to population density. 
Colouring up, Ram fry at 8 weeks old. Photo by: Andy There may be some temptation to increase the speed of growth, this can be achieved by feeding a high protein diet and increasing the fishes metabolic rate through higher temperatures. Fast growth should be left to the fish 'puppy mills'. Not only will an increased metabolic rate mean that the fish are doomed to shorter lives, high protein foods can cause internal health problems in the future. Enjoying watching your fry go through the various stages and grow into beautiful healthy specimens is an amazing experience and one you will be proud of. Your lfs will also be very pleased to take well raised healthy young fish too. 
Adult Male Ram. Photo by: Andy Back to Ichthyology | 
