Water changes

[fatdiscus]

Hello everyone,
I'm trying to grow my first batch of discus. They're going to be in a 48x18 tank soon. How often should I change the water for the best growth, and how much of the water should I change. I've read that Penang breeders change up to 90% twice a day. That seems a little excessive to me, esp with the drought and all. Would say, 66% every second day be ok, keeping in mind I want a good growth rate.
Also, I do COLD water changes of 50% with the adult fish. They seem fine. Will this be ok for the baby fish also?
Thanks
Fatty

[samir]

better 33% daily than 66% every two days.
depends on how many fry you have in there. if its 400 then maybe you need a 90% water change.
dont try the cold wc's with fry, as a matter of fact you shouldn't be giving adults a 50% cold wc either. the water in Sydney drops to around 56f nowadays so unless you're in the tropics I wouldn't recommend it.

[discus lover01]

i would be doing at least 25% daily changes in the tank but again as samir said it depends on how many dicus you have and there growth will also depend on how many discus are in the 1 tank 4ft tank is around what 200 litres thats about 5 discus as they require aprox 40 litres each fish to get get optimum growth and if you over crowd it then you will find you get slow growth.
thanks
brett

[fatdiscus]

thanks for the responses
Why 33% daily rather than 66% every second day? Is it to remove waste and mulm more frequently, so that it doesn't leach so much pollutant back into the water?
I've counted about 50-60 fry, give or take. Can I grow these up until the first cull, say at 6cm, or will I need to split them up. I definately don't want to stunt them.
Cheers

[discus lover01]

the more frequent water changes the better and it helps keep water at optimum levels also if you ahve that many fry i doubt you will be able o hkeep all together until 5-6cm and the first cull as there will be just to many different sized fish and before this you may need to move larger fry out to different tanks to help with even growth other wise u get 6cm ones and then 4cm ones as the ones are pigs and keep smaller ones away from food so you will need to move them around well b4 the 6cm mark.
hope this helps

[mcloughlin2]

You could grow up 50 fry in a 4x18x18. I've seen it done heaps of times on this forum and others. Basically you need to do WC's daily to remove excess waste and nitrites. Every other day WC's are not as good becauise your leaving all the waste etc in the water for longer periods of time.

I would do the first cull at 3-4cm. Cull any fish with noticable deformaties at this stage.

I don't believe there is much difference in growth rates between discus fry. Removing the smaller fry won't solve the problem either as there is always going to be less dominant discus being picked on.

Just make sure you feed the food at intervals along the tank so all discus can easily get to the food.

Sam.

[samir]

your 50 fry will be fine, you may need to get a drum for water. as they grow bigger you will need to change more water. With a bit of practice you'll figure out how much they need per day.
it will be of great benefit to get a uv steriliser, if the parents are not clean,discus fry can drop dead like flies once they reach around an inch. with the uv that is less likely to happen.