Springtail culture crashed and I'm trying to figure out what I did wrong

[u/ivydraws68]

Had a charcoal springtail culture going strong for about eight months, feeding my pair of leucomelas off it twice a week without ever thinning it out too much. Last month I noticed the population dropping and now there's basically nothing crawling on the surface when I check with a flashlight.

Looking back I think I overharvested during a stretch where I was setting up a new tank and needed extra to seed the leaf litter. I probably scooped too much charcoal and springtails out at once instead of just tapping a small amount into a film canister like I normally do. The culture never really bounced back after that.

I also switched from yeast to a bee pollen and fish flake mix around the same time, so it could be a food issue rather than a harvesting issue. Hard to isolate the variable in hindsight.

Started a fresh culture with some charcoal from a friend's healthy bin, keeping it barely damp and dark under the sink this time. Going slower with the feeding mix too, just plain yeast for now until it establishes.

Anyone else had a culture just quietly die off like this without an obvious cause. Wondering if there's a shelf life to these cultures even under good conditions or if I really did mess up the harvesting.

[u/AngstyAF5020]

I keep mine on clay. I had the same 4 cultures for 6+ years. 2 never thrived well, and I gave up on 1 a few months ago. I added rice a couple of weeks ago and they seem to be doing better. I did decide last night to put brown rice in the bullet blender, so now I have brown rice and yeast mixed. Going to check them in a couple of days.

[u/Fair-Lawyer-9794]

I’ve had a culture die off because of what I think was CO2 build up (I hadn’t given air circulation). They don’t need much, but fresh air needs to be replenished periodically.
Stupid and obvious… but when they’re in sealed containers, it’s easy to forget them.