Death toll rising :(

[jimscott]

What Elgecko said is dead on. I tried an experimenting with replacing the water from existing tanks, but with new filter media. It staves things off temporarily. Seasoned filter media with new water is far superior to "aged water" and new filter media.

Nitrosamonas bacteria break down ammonia into also toxic nitrite. then nitrobacter bacteria break down the nitrites into safer nitrates.