Growth in fish is determined by many factors both physiological and environmental.Factors such as parentage,sex,diet,water conditions,
age, Maturity, Temp etc. All of this can impact total growth for a given year by an individual fish. Fish in captivity are on a very
different water change and diet schedule that those in the wild. One they get 100% waterchanges daily and two they forage at will. They
also have an open ability to select optimal habitat.
In captivity they do not receive the same conditions. We generally feed our fish in a manner best described as "stuff and starve". They
receive a set amount of food and that's it. This does impact growth. Small bodies of water are also more likely to concentrate wastes
much quicker. I do not care how much filtration you have or how many waterchanges you do a week, you can not replicate natural water
conditions in captivity. Co-habitation with other fish in a small system also impacts the fishes growth through psychological stress as
well as competition for food and living space.
Some specimens of Polypterid for example P.endlicheri are capable of reaching 19 inches in one year however it is much more common for
them to reach 10-12inches(see below)during its first few months of growing and then slow until it seems to have stopped and growth then
can occur in bursts.
POlypterus e.endlicheri
30-45 days 1.1-2.6 inches (2.8-6.5 cm) long.
70 days of age the fry were 3.8-4.2 inches (9.5-10.5 cm)
180 days they were 5.2-6.0 inches (13-15 cm) long
300 days they were 6-8 inches (15-20 cm) long
*At this point sex of the fish will determine growth to a large degree. Female will grow quicker, thicker and larger throughout each
season up to year 6. Males pretty much slow down or stop growing much after the 3rd year. At this point some males are reproductively
active.
To help your fish reach its maximum growth potential try the following
Nutrition-Quanity and quality which is one reason i suggest adding a good quality pellet to a varied diet this insures they get they
needed vitamins.Several small meals thru the day are better than 1-2 big meals,smaller meals allows them to scavage thru the day as they
would in the wild
Genetics-not much you can do here but hope they are good
Salinity,pH and hardness-avoid huge swings in any of those parameters
Temperature- keep water temps in low 80sF this will slightly speed up the metabolism rate allowing food to digest faster.
light-maintain a constant light schedule install a timer if you must
Waste-Keep the tank clean and maintain the best water quality and water change schele you can.Rememmber biological filtration
only removes ammonia there are a myrid of other substances that are removed only during water changes
Tankmates-Beware of over agressive tankmates out competeing less agressive tankmates for food.
Growout tanks-consider using a growout tank for very young(small) bichirs a ten gallon is good for this as it allows them to exercise
and makes finding food stuffs easier so they can use the energy for growth then molve them to a bigger tank when they get about 7 inches
The real question about growth is since we are supposed to be providing them optimum conditions why they don't necessarily grow larger?
*Using P.endlicheri for example only.Some smaller polypterids are sexaully mature after 1 year
age, Maturity, Temp etc. All of this can impact total growth for a given year by an individual fish. Fish in captivity are on a very
different water change and diet schedule that those in the wild. One they get 100% waterchanges daily and two they forage at will. They
also have an open ability to select optimal habitat.
In captivity they do not receive the same conditions. We generally feed our fish in a manner best described as "stuff and starve". They
receive a set amount of food and that's it. This does impact growth. Small bodies of water are also more likely to concentrate wastes
much quicker. I do not care how much filtration you have or how many waterchanges you do a week, you can not replicate natural water
conditions in captivity. Co-habitation with other fish in a small system also impacts the fishes growth through psychological stress as
well as competition for food and living space.
Some specimens of Polypterid for example P.endlicheri are capable of reaching 19 inches in one year however it is much more common for
them to reach 10-12inches(see below)during its first few months of growing and then slow until it seems to have stopped and growth then
can occur in bursts.
POlypterus e.endlicheri
30-45 days 1.1-2.6 inches (2.8-6.5 cm) long.
70 days of age the fry were 3.8-4.2 inches (9.5-10.5 cm)
180 days they were 5.2-6.0 inches (13-15 cm) long
300 days they were 6-8 inches (15-20 cm) long
*At this point sex of the fish will determine growth to a large degree. Female will grow quicker, thicker and larger throughout each
season up to year 6. Males pretty much slow down or stop growing much after the 3rd year. At this point some males are reproductively
active.
To help your fish reach its maximum growth potential try the following
Nutrition-Quanity and quality which is one reason i suggest adding a good quality pellet to a varied diet this insures they get they
needed vitamins.Several small meals thru the day are better than 1-2 big meals,smaller meals allows them to scavage thru the day as they
would in the wild
Genetics-not much you can do here but hope they are good
Salinity,pH and hardness-avoid huge swings in any of those parameters
Temperature- keep water temps in low 80sF this will slightly speed up the metabolism rate allowing food to digest faster.
light-maintain a constant light schedule install a timer if you must
Waste-Keep the tank clean and maintain the best water quality and water change schele you can.Rememmber biological filtration
only removes ammonia there are a myrid of other substances that are removed only during water changes
Tankmates-Beware of over agressive tankmates out competeing less agressive tankmates for food.
Growout tanks-consider using a growout tank for very young(small) bichirs a ten gallon is good for this as it allows them to exercise
and makes finding food stuffs easier so they can use the energy for growth then molve them to a bigger tank when they get about 7 inches
The real question about growth is since we are supposed to be providing them optimum conditions why they don't necessarily grow larger?
*Using P.endlicheri for example only.Some smaller polypterids are sexaully mature after 1 year
