I goofed and killed 3 of my fish changing water.

I have a 36 gallon. I did a complete 100% water change, washed the gravel, cleaned the pump, but did not wash the large bubbler or the plants. Refilled with hose waer, put in stress coat and anti algae (a little heavy on stress coat) waited 18 hours for temp to equalize, and reintroduced fish. 3 goldfish, 2 plecos. This was Thurs. Today, all 3 goldfish bit the dust. Plecos seem fine for now. Chemical smell coming from water. Ph was a little high (7.5) and no ammonia. What happened and how do I save my plecos?

 

Why did you do 100% w/c? Or wash the gravel? That means lots of your BB is gone, and by cleaned the pump you mean the filter?

Is your tank cycled?

 

What is this anti-algae stuff you speak of? Algacide can kill fish very easily.

So can water with low oxygen if you do a 100% water change with it. You will see the fish gasping and suffocating if this is the case.

Also, adding too much dechlorinator can use up all the oxygen in the water (depending on what else is in your water) and can cause a fish kill. You will also see the fish gasping and suffocating in this case too.

 

I would do a 50% or 75% water change

'chemical smell from water' is very suspicious to me.

It sounds like a dosage issue.

 

Was there an issue you were trying to deal with? Why did you clean everything?

 

When you say that you filled the tank with water from a hose, was that hose approved for drinking water use? Typical garden hoses leach plasticizers that could be harmful to fish, and also to you if you drink water from the hose. Clear PVC tubing is usually safe as are hoses made for use with recreational vehicles for potable water.

Also, by you through cleaning, you wiped out any beneficial micro-organisms you may have had in the tank. These organisms are a necessary part of the aquarium..

 

When my tank was more stocked, I did a 90% water change weekly with thorough gravel vacuuming and thoroughly cleaning filter media with tank water, every single week. I drained the water until my fish just had enough room to stay upright. I never had an issue doing this.

I'm doubting it's the large water change but rather something to do with the water quality. You said there's a chemical smell from the water? Does it possibly have to do with that algae treatment product you've used?

 

I wonder if the water supply is treated with chloramine. That is a combination of chlorine gas and ammonia which is now being used by many water suppliers to disinfect the water supply. When changing nearly all the water, the tank was refilled and then the water conditioner was added. That means the fish were exposed to chloramine for a period of time. It would have been better to treat the water with dechlorinator in a bucket before adding it to the tank. However, dechlorinator breaks the chloramine bond and then reduces the chlorine gas to non-toxic chloride ion. However, it does nothing to reduce the toxicity of the ammonia.

Ammonia (around 1 ppm) has to be processed by nitrifying bacteria to convert it to nitrites and nitrates. However, by doing a deep clean of the tank, a significant portion of the nitrifying bacteria were removed. Thus, the fish were subjected to ammonia which can weaken or kill them.

For anyone who has tap water containing chloramine, I recommend that water changes be less than 20%. That would result in ammonia levels around 0.2 ppm, which is still higher than ideal, but not so high that fish will be killed. Also be sure that the tap water is treated prior to introducing it into the aquarium.

 

OP has vanished?

This is so tragic. The guys was told to so often to change his water for the fish, and in doing so he has killed his fish.

Ray is right that with Chloramines in water now and so many places adding them without telling people, water changes can become deadly. The old advice of 'change the water' just is not up to snuff any more.

And so many wells like mine have low oxygen so changing water can kill fish that way too.

Water really needs to be pre-treated and tested nowdays to make it fish ready. We have to assume the water is bad, and only use it for fish once proven that it is fish ready!