Discussions

Calling all outdoor pond enthusiasts. Our Koi and goldfish have died on us again.  
We prepped the indoor tank by aerating the water with a chlorine remover and let it run for a week empty. Then ran empty for two weeks with the charcoal filter. We kept the fish in a cooler with a bubbler while adding tank water to the pond water that the fish were in. They have been in this tank for over a month doing well. Actively swimming and eating.  
(/BUT) in 12 hours the water has gone milky and three dead fish. Any suggestions out there as to what is happening and why?

Take a sample of the water. Test it for ph. Ammonia. Nitrites. They say any aquarium should have a 10% water change every ten days also too keep these levels lower. In your outdoor pond there's plants that help with these things usually. The confines of your indoor tank get dirty quick.

If there is still fish alive. Water change imodeataly. Maybe once today and once tomorrow. Deffinitly test your water though.

A amount of pond substrait and a little bit of food could help the nitrates and nitrits going. sounnds to me that there was no biologic cycle going when you put fish in and you had a nitrite? bloom that killed fish. or somthing like that

I have always added some pond water when I do the transfer, the same as I have done for the last 15 years. We do check our ph levels.They were good. Did a complete water change, So far only lost two out of six.

I transfer my pond water to fill the entire storage trough for wintering the koi...I just use a small sump pump and hose and fill it up. Then I have a filtration system that I made with a Home Depot bucket, some hoses and foam. That adds enough oxygen but I’ve also added a small bubbler to ensure they’re well oxygenated. I’m not certain what’s happening with your fish. I once had a white coloured water which killed all of my fish but I had added some coral for decorative reasons, but it leaked the toxic milky substance that was deadly. I have mesh covering my indoor trough as my koi seem to like to jump out. And, I do regular water changes.

Do you transfer any biological media when you move your fish indoors? The biological media could be the gravel from the bottom of the pond, or any used filters from the pond. This is where the bacteria lives that turn ammonia into nitrites, and then into nitrates. Putting some of the old water into the indoor tank wouldn't be enough as very little of the bacteria live in the water column. Without the bacteria in the indoor tank your fish might be dying from ammonia and/or nitrite buildup, both are very toxic to fish. The best way to know would be to test your water for each. Ammonia should be 0 ppm, and nitrite should be 0 ppm.