DISINFECTING YOUR AQUARIUM
Anytime you experience a severe outbreak of disease where you lose fish, I recommend disinfecting your aquarium. I couple years ago two of my tanks were devastated by an outbreak of Columnaris a bacterial disease that is next to impossible to cure.
The process I used for disinfecting my aquariums was very successful. It's also a good practice to do this when purchasing a used aquarium just to be safe.
I began with the 55 gallon. It took me most of the day to get both tanks running with bleach water.
I removed everything from the tank. Beginning with my HOB filters and canisters, throwing out the media, I soaked the containers and hoses in a large pail of bleach water while I worked on the next step.
I removed the thermometer, heater, decor, power heads and my UV sterilizer. Washing each item down with bleach water including the electrical cords and plugs. Anything I could soak I did. I also removed about 1/2 of the substrate and let that sit in bleach water as well.
Once the aquarium was empty of everything, including the water, I washed the black trim of the tank, the lids and glass using bleach and water again and a soft brush. I then began to refill the aquarium with fresh water. I added bleach to the water after the tank was full. The rule of thumb for disinfecting anything with bleach is, You only need to add enough that you can faintly detect it's scent. Once the lids were on it wasn't noticeable.
Having the tank ready I returned the decor that I was keeping, the HOB filters, the UV sterilizers heaters, power heads and thermometers to the freshly filled tanks. Turning the filters on I let them run for over 24 hours. Allowing the bleach water a chance to flush through everything.
It's also very important to soak your nets, containers and anything else that may have been used on the tank. Brushes and scrubbies are best discarded and even the food that fed the sick fish should be tossed. I know this sounds extreme but after going through that devastation nothing could be overlooked.
After both aquariums ran with bleach water for over 24 hours I felt they were safe to use. It was time to neutralize the bleach. I began dosing with Seachem safe. Once the bleach was gone I then began cycling both aquariums.
I use a no fish cycling procedure. I will leave a link to that video in the description below. This process is no fun but it will ensure your tank is free of any bacteria that may harm your fish. To avoid passing on any illness from one tank to another it's important to have separate sets of food, nets and anything else you use for each aquarium.