umm this is odd....

i did my weekly water change today. i did about 20 gallons out of my 65 gallons.

all my fish keep going to the top of the tank now. this has never happen b4 after a water change.

my angel fish in the tank are all at trhe top of the tank. my plecos keep going up for air..


i didnt change anything but the water....... what do i need to do ?

add air, they are after oxygen.

Add in an air stone and run it hard!

Are you still doing your water changes with coldwater?

Have you done any water tests and is your filtration running normally ?

my sump is working fine.

i got up this morning and all fish are fine. all my angels are hungry like normal and all pleco are chewin on the wood.

i dont know what i did different. the water was not cold but not hot... close to room temp.

It's possible that the 30% water change started a mini cycle.

see when yall talk about doing too much of a water change. i dont believe this since in my discus tank i can do a 100% water change and the tank will be fine within hours... the fish kind of stress when i do it but it is possible to do.

i have had my discus tank up for over a year and a half. i have been doing 60-80% water changes every day for the first year. till i added some more water volume. no i can let it be for a week.

so i know its not the amount of water i changed. but thinkin back on the water itself that was put in the tank..... the water was white looking. like a cloud in it kinda. but i didnt think nothing of it till this morning. this isnt normal for my tap water so it dosnt happen all that often. but it does happen.


i think im going to fix this by aging my water out side. i ordered 6x55 gallon drums. some of them are going to be a water filter for my pond and some of them will be a rain water catcher for my plants/pond.

Hi just two things i can think of and that is the water may of been too warm when you added it and do you add water conditioner before you add the water?

yes i add water conditioner. i actually added 3 caps of it. one cap is for 55 gallons. i added more to reduce stress of my new pleco trio i just got 3 days ago.

the water was around room temp which is cooler then the water in the tank. but not cold. i introduce cold water normally since this is how i simulate the rain.


this is the funny part. i have my original pair in a 20 gallon long now. i still add only cold water to the tank. this pair is now spawning for the 2nd time.

i treat both tanks the same. but the 60 gallon with my new pair in it is the one acting weird.

This statement gives me concern

(see when yall talk about doing too much of a water change. i dont believe this since in my discus tank i can do a 100% water change and the tank will be fine within hours... the fish kind of stress when i do it but it is possible to do.)

Stress will eventually trigger disease in otherwise healthy fish. While you think your fish are fine it's a just a matter of waiting until you do have a problem.

Was wondering if you test your water on a regular basis ?

I agree with Jim and think you probably triggered a mini cycle. I'd be on the lookout for an ammonia spike. You could possibly even be killing off your biological activity if you are not careful with your waterchanges.

I myself am more comfortable with small water changes often as opposed to one large one.
Taking care of the water in the long run takes care of your fish

well my discus have had no issues with this type of water changes.


i think the aging of the water will help with this problem in the future. im also going to build a new sump. instead of using a 10 gallon tank and only using 5-6 gallons of it. i will be building a 30 gallon and using 22-25 gallons of it.

making my tank close to 85 gallons total. this way i can keep doing my 20 gallon changes when i vacuum the debris in the tank

Have you considered adding a good mechanical filter such as a Fluval to your tank ?

It would work in conjunction w/your existing sump which I'm assuming functions more
as a biological filter than mechanical while a Fluval can function as both

It could easily give you a break from these large water changes

my new sump i am building my self has a filter sock in it. so this will be the mechanical filter. but i still have stuff in the tank that doesnt float to the top where the skimmer will pick it up.

Aleishoo is right about large water changes stressing your fish.

The larger the water change the greater the risk that the water chemistry will change dramatically, putting stress on the fish.

Why do you have to do 80-100% changes with your discus ?

I would say a large water change is like leaving your front door open in the winter for an hour and then
closing the door and waiting for the house to warm back up so you can stop shivering.
If you are in good health, maybe you won't get a cold or the flu. Extreme example but....


Cold germs and humans are like what Ick /etc is to fish. They are usually there but only become a problem when stress is a factor.

and keeping fish should not be such hard work.
If it was, I wouldn't do it.

I know some people who do 25% wc a week on well established tanks over 100 gallons but they do this consistenty and have top of the line equipment on their tanks and test their water daily.

Hope this helps

ahhh, this old chestnut.

Quote :

Why is it that discus breeders can do massive water changes and I can't

The simple reason is the same that you can do huge changes on a siamese fighing fish bowl, their tanks are not cycled, they are not meant to be. We spend heaps of time trying to get the cycle right in our tanks where as discus breeders do not have time or the hardiness of the fish for this so they never let the tank cycle, they do regular large water changes so that essentially any waste products are removed from the tank before they can turn into toxic ammonia or if they do they are removed straight away. Most discus breeders will do 50% every day or every other day, meaning that in 2-3 days 100% of the water is changed, meaning there is never a chance for any ammonia to build up, meaning there is never any cycle, meaning there is no cycle to mess up.

on the flip side, most normal tanks run with a fully functioning ecosystem of bacteria in there filters which does not deal with large water changes and will cause the tank to cycle.