The Basics of Raising Fry -- Health
By: Victoria Stark
Submitted: 1/10/2004
By: Victoria Stark
Submitted: 1/10/2004
2 week old betta fry (Karen MacAuley)
Usually, if you keep the water quality good, rinse live food well, and don't do anything silly like net-sharing, your fry should stay pretty healthy. However, sometimes the worst happens and an outbreak of disease can wipe out an entire spawn if you're not careful. It just takes one sick fry to kill a whole batch, so watch for the signs. Fin-clamping, lethargy, and sudden die-off can mean a problem in your fry tank. An occasional dead fry is normal, but several of them dead every day means trouble. We lost many fry one year when there was a problem with harmful bacteria in our local water source. The paper published a suggestion for residents to boil their water, and like an idiot I completely underestimated the affect of the unboiled water on the fish. I lost many fry to bacterial infection before it dawned on me what was going on. So you just never know, and even the most careful betta breeder will have to deal with sickness at some point in time.
Fry in particular can be difficult to diagnose. Make allowances for a sudden die-off at around the 10-day mark, as fry absorb the last traces of their yolk sac and either hunt or starve. Don't be alarmed, it's a natural process. Just remove dead fry as soon as you see them so they don't pollute the tank.
Most of the remedies outlined in the section Betta Health and Care can be used on fry. Velvet is the most common lethal disease of fry, but it can be kept in check by keeping a half teaspoon of aquarium salt to every gallon of water in the fry tank at all times. Great fluctuations in temperature will weaken fry and make them susceptible to many diseases like parasites, fungal infection, bacterial infection, and just about everything else under the sun. The number one fry killer is water pollution caused by overfeeding and infrequent water changes, so be careful not to slack off in those duties.
If you do suspect outbreak of disease in your fry tank and don't know what is causing it, I recommend jarring the largest and best individuals until you can figure it out. This makes them easier to observe, and keeps them from getting sick (if they aren't already). That way, if you do end up losing the entire spawn, at least you'll have saved the best individuals, so its not a total loss.
When you have diagnosed the disease, treatment can begin. Most treatments take a few days to a week to complete, and usually several doses. Once treatment is complete, I would recommend moving all of the fry into a new tank full of clean, same-temp water, to prevent reinfection. If they are very small, you can siphon out about 90% of the water and catch them with a brine shrimp net. Completely strip and disinfect the old tank before using it again.
Fry in particular can be difficult to diagnose. Make allowances for a sudden die-off at around the 10-day mark, as fry absorb the last traces of their yolk sac and either hunt or starve. Don't be alarmed, it's a natural process. Just remove dead fry as soon as you see them so they don't pollute the tank.
Most of the remedies outlined in the section Betta Health and Care can be used on fry. Velvet is the most common lethal disease of fry, but it can be kept in check by keeping a half teaspoon of aquarium salt to every gallon of water in the fry tank at all times. Great fluctuations in temperature will weaken fry and make them susceptible to many diseases like parasites, fungal infection, bacterial infection, and just about everything else under the sun. The number one fry killer is water pollution caused by overfeeding and infrequent water changes, so be careful not to slack off in those duties.
If you do suspect outbreak of disease in your fry tank and don't know what is causing it, I recommend jarring the largest and best individuals until you can figure it out. This makes them easier to observe, and keeps them from getting sick (if they aren't already). That way, if you do end up losing the entire spawn, at least you'll have saved the best individuals, so its not a total loss.
When you have diagnosed the disease, treatment can begin. Most treatments take a few days to a week to complete, and usually several doses. Once treatment is complete, I would recommend moving all of the fry into a new tank full of clean, same-temp water, to prevent reinfection. If they are very small, you can siphon out about 90% of the water and catch them with a brine shrimp net. Completely strip and disinfect the old tank before using it again.
