Death during Cycling

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JEAE21

Feeder Fish
MFK Member
Aug 19, 2007
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What kind of fish can survive the cycling period, if I do 50% water changes weekly during that time?

What kind of fish would die instantly?

Would small knifefish, ID sharks, silver dollars, and oscars survive?
 
I would use something small and hardy.
Giant danios, gouramis, etc.
After the cycle, trade 'em in, or leave 'em in, no matter.
What size tank you talking here.
 
Don't do water changes during the cycling. You're defeating the purpose. You want the ammonia to build up and change to nitrite then nitrate. Changing the water is only going to make it a longer process.
 
If you have to do water changes during the cycling it means you started with too many fish:eek:

By all means monitor the water, and if the ammonia or nitrite gets too high or the fish look stressed out, THEN do a 50% water change. It will mean the cycle is going to take longer, but it should save your fish.

Best if you have less fish and just let things happen slowly though.

Pick fish that are small, hardy and easily replacable, they should survive fine. Anything big, delicate and expensive is practically certain to die on you :cry: Something like a knife fish would be a BAD idea to start with, add that after the tank is fully cycled.

Cheers

Ian
 
it's a new 240.

and i was also wondering about my 40 that already has fish in it, and i got a new filter(while still running my first filter) for it so i wondered if the sunfish, guppys, and goldfish are gonna be alright or not..

but in my book it said to do atleast a 50% once a week during cycling..(??!!)

hey ian, how will i know if my fish are stressed out?



oh, and i have a whisper 40i running in the 40...i think it was very clsoe to cycling and then i got a new XP3 with a bunch of bio media.
would the bio floss in the 40i kill up all the ammonia before the XP3 sucks it up?
 
can you test your water parameters daily? thats what i do during a cycle to see where im at in the process--if your levels are too high you can do smaller waterchanges to help ease the stress of the cycle..

signs of stress include flashing, gasping (rapid breathing), color could be a little off, fish that aren't eating and of course the obvious one--multiple deaths.
just keep an eye on all of them and dont overfeed them during the cycle..
what are your parameters now?
oh, and bio floss wont kill any ammonia floating around in your tank..
 
Doing water changes during the cycling wont hurt the fish, it will just make the cycle take longer. But if you have too many fish in the tank, then it's a good thing. It will slow down the cycle, but keep the fish alive.

Like Navygirl says, if the fish are faded and gasping in the corner instead of swimming about and eating normally - then they are stressed and something is wrong. If they start doing that, then do a big (50%) water change right away. If they are swimming about and acting happy and healthy, then they probably are.

You have to find a balance between putting enough bioload (ammonia) into the tank to feed the filter bacteria, and adding too much. If it builds up faster than the bacteria can multiply it will kill the fish.

When I set up a new tank I allways try and get an established filter or some filter media from an established tank. That way you are moving a usefull population of bacteria into the tank right at the start. You can run an extra spare filter in another tank all the time. Then when you set up a new tank, move the small cycled filter in when you add the first fish. The spare filter doesn't need to be big enough to handle the new tank by itself, just the amount of fish you add to start with. You still have to take things slow and add fish over several weeks while the new tank and filters cycle, but you shouldn't have any dangerous spikes or loose any fish doing it that way.

Cheers

Ian
 
JEAE21;1245899; said:
it's a new 240.

and i was also wondering about my 40 that already has fish in it, and i got a new filter(while still running my first filter) for it so i wondered if the sunfish, guppys, and goldfish are gonna be alright or not..

but in my book it said to do atleast a 50% once a week during cycling..(??!!)

hey ian, how will i know if my fish are stressed out?



oh, and i have a whisper 40i running in the 40...i think it was very clsoe to cycling and then i got a new XP3 with a bunch of bio media.
would the bio floss in the 40i kill up all the ammonia before the XP3 sucks it up?

Water changes during the cycling period defeat the purpose. Title and author of your book?
 
navygrl; what?? so that bio floss in my whisper 40i is just a tray doing nothing...RIP OFF!! (but it did get the tank cloudy though)
i can't test them now, but i will go get some test strips.

ian; normal cycling takes 6~8 weeks right?! what if I do water changes? should I lower it to 25% weekly?
O.k. I'll leave the water alone in the 240 but in my 40gallon I already have some fish in it...and my new filter is just "smoking the tank" and don't want to kill the fish.

post #9; what are you, trying to act like a cop now oh give me your title and author of your book....
and you just repeated what ziggy2 said in post #3...yet AGAIN, trying to find an excuse to post in my thread with non-helpful information.(helpful when ziggy says it!)
 
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