Backyard Aquaponics
A place to discuss aquaponics

If I save the grow media and don't let it freeze in the winter, can I start up my system in the spring with no ammonia cycling? How resilient are the nitrifying bacteria in the grow media?

Probably, as long as you keep it moist and out of direct sunlight. It doesn't need to be sitting in water the media only needs to be damp. I've had them last for about 6 months in their original plastic bags during a breakdown, move and rebuild - no cycling once restarted. They were removed from the old setup and were damp because of this but that was all the moisture they had (the bags kept them damp but had a few holes so they weren't perfectly airtight). I'm sure some organisms do die but they probably make food for the others in the process.

I know for saltwater systems keeping live rock damp and wet helps to keep the bactria alive to help with cycling tanks Im sure this would be the same for the media in a way. live rock is shipped damp and in dark containers away from light to prevent bactira kill off.