cherry shrimp colony out of control in 20g

[w0lfpack88]

So I've had this 20g planted tank running for about 8 months. Started with like 20 cherry shrimp from a buddy, and tbh it was slow going at first. Params were spot on: TDS 150, temp 72F, heavy leaf litter and cholla for biofilm. But last month? Boom. Woke up to hundreds grazing everywhere. Shrimplets by the dozens, berried females stacked up in the moss.

ngl it's awesome but I'm stressing overcrowding. Nitrates creeping to 10ppm even with 50% weekly changes, and some adults look lethargic. Saw that colony guide thread, followed most of it.

https://aquariumowner.com/threads/cherry-shrimp-care-guide-from-colony-to-empire.21

Thinking of grabbing a couple 10gs to split 'em. Anyone done this? Best way to thin without stressing the colony? Cull some juvies or just net and relocate? Pics attached if it helps.

Tank's got java fern, moss balls, floating plants. Food is Shrimp King and blanched cukes. Hit me with your splits stories.

[FreshwaterFan]

10ppm nitrates is honestly not that bad for cherries, I've seen colonies thrive in way worse. The lethargic adults worry me more than the number tbh. Are they actually sluggish or just hanging out in the moss not moving much? Because mine do that after a big molt wave and it freaks me out every time.

Anyway I did the split thing last year with a 20 long into two 10s. Biggest mistake was trying to net the juvies. They're basically invisible and I ended up chasing shrimp for like an hour, stressing everything, and I lost a few. What worked better was dropping a piece of cuke in a net and just lifting it out when they piled on. Way less chaos.

But heads up, the new tanks need to be cycled and mature or you'll get die offs. I rushed one of mine and lost a bunch of shrimplets in the first week and I felt terrible about it. How long have your 10gs been running? Do you have a sponge filter seeded from the main tank you can use?

Also 72F is on the cooler side, that might be why they slowed down a bit. Just a thought.