is there such a thing as too much water changes??

FroggyFox

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May 16, 2003
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#2
I think there is a certain point that you have too many water changes. Is there a REASON that you're doing it so often? Usually water changes need to be regular, and are mostly to remove waste and nitrates from the tank. If levels of waste and nitrates are ok (not clouding the tank and nitrates under 10ppm) then there isn't really a reason to do a water change.

Exceptions would be having medication in the tank that you need to take out by doing water changes...or something in the water that you need to remove.

Potentially too many water changes too often could harm your fish because of the stress/shock to their systems.

SOME fish have to have regular water changes like Discus...so a lot depends on your water conditions, the size of your tank, which fish you have etc.
 

denon31

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Aug 6, 2003
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#4
IMO, there's nothing wrong with doing water change daily. theoretically, it should be good for your fish since it gets a new supply of cleaner water. however, you still have to consider the stress that your fish will go through every water change since you will be adding new water that the fish hasn't felt yet. that's why sometimes it's better to perform water changes with longer intervals. and like what froggyfox said, if the water still is OK then there's no need to change it because you may only stress your fish in doing so.

as long as are sure that you can minimize the stress on your fish, then daily daily water changes aren't bad. in fact, i know someone who does 100% water change daily. 50% in the morning and 50% at night. and i hear it does great for his fish.
 

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tetra girl

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#5
i wouldnt do any more then a 20-25% water change each week unless you have discus or fry.

Water change stress out the fish as you usually use a siphon to get the water out and then add it with buckets. The water is the buckets will usually be different to the water that is in your tank.

Yes in the wild they do get daily water changes in the form of rain but you have to remember that rain is very unobtrusive and so doesnt stress them out. also as the rain washes in to the river it washes peat and stuff with it.
 

Jul 25, 2003
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#6
thanx, i never knew it could...i have always told myself to keep the tank as clean as possible, meaning everyday water changes....i thoguth its gonna simulate the natural repleneshing of the water..i have been trying to read about this, and no luck..this shud be included in water maintennance artilces...:)

i guess too much of everything is bad.
 

Apr 11, 2003
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#7
To: denon31

Two 50% water changes does not equal a 100% water change. Your taking out the same amount of water but not the same amount of old water the second 50% takes out 1/2 of the new water from the morning and half othe water from other days.
 

1979camaro

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Oct 22, 2002
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#9
adendum: you can never get all the original water out, unless you empty the tank...its like if you keep taking steps to a door, but each time you decrease the length of your steps 50% of the distance remaining you will never reach the door
 

Jawz

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#11
id still like to know what tank ur doin the daily water changes for and what fish are in there....

but i see if ur parameters stay and 0, nitrates 20 ppm or less is better, your pretty good. My tank is little packed so now im doin 30% weekly changes to keep nitrates lower.
 

denon31

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#12
Originally posted by rocketshrimp
To: denon31

Two 50% water changes does not equal a 100% water change. Your taking out the same amount of water but not the same amount of old water the second 50% takes out 1/2 of the new water from the morning and half othe water from other days.
oops... i guess i messed up my math this time. my bad :)
 

Somonas

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Oct 22, 2002
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#13
As far as I am concerned, if the PH and water chemistry is close enough, so as many as you'd like. I actually tested it today and I find I can do about a 50% waterchange in the smaller tanks and the ph only goes up 0.4 or so. which is about all fish can take.

That being said I keep all of my tanks neutral, so I have to be really careful when changing small tanks, fry tanks or mouthbrooding tanks.
 

denon31

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#14
camaro, it is possible to change 100% of the water without having to empty the tank... but it's gonna take some time.

to do it, just have a steady flow of incoming water while syphoning your tank. you can do this with a water hose or something. then make sure that the amount of water leaving the tank is equal to that of the water entering it so you get to maintain a steady water level in the tank. do this for an extended amount of time and you'll surely get to change close to 100% of the water.

IMO, this is a very good way of changing water. since doing this simulates running water, you won't stress the fish too much since it'll slowly feel the new water, unlike when you pour water from a bucket where the change is so sudden. more importantly, you'll get to change almost 100% of your water.

just my two cents... :)
 

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Jul 25, 2003
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#15
well, here are my parameters
75 gallon
ammonia:0ppm
nitrite:0ppm
nitrate:0-5ppm

Kh:6
Gh:14
ph:7.8(taps is 8.0)

Fauna: 10 tiger barbs
20 danios(this will have to go once the fish starts to ge bigger)
3 siamese algae eater
2 bala sharks(baby)
1 red tailed shark
1 syno eupterus catfish
prolly some snails(one of my dads friends who works as an aquarist profesionally told us to add snails to control algae and that the bala sharks will keep them under control, so he gave us some baby snails).

Right now, im having problems with green cloudy water. I just recently added a few bulbs so its prolly lighting).

I change water daily cos i really thought its gonna help the fish alot.

edit:i use a hose to transfer water as 15 gallon is heavy:)
 

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AndyL

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Oct 22, 2002
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#17
Originally posted by Igor The Cat
yes ther is such because you could sterss the fish to death and kill a LOT of good bacteria
Igor - no offense, but you don't have a clue...

The only way you're going to stress your fish out by too much/many water changes is if the water change water is of different condition than what is in your tank. Meaning, pH, gh/kh, and temperature all need to be the same.

With discus we do this by ageing water. Basically we prep the water the day before we need it. By aggitating it and heating it for the 24 hours before the water change.

The only way you're going to kill bacteria by doing water changes is by failing to dechlorinate (and ageing water by itself will dechlorinate - just wont get rid of chloramines).
 

AndyL

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Oct 22, 2002
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#19
Originally posted by Igor The Cat
i know many people who killed fish by useing the old bucket method with sensitive fish
Originally posted by AndyL
The only way you're going to stress your fish out by too much/many water changes is if the water change water is of different condition than what is in your tank. Meaning, pH, gh/kh, and temperature all need to be the same.
I rest my case...