Southern toad tadpoles... Seizures? Tail chasing?

[Sherlock]

Hi! I have zone southern toad tadpoles taken from a retention pond bordering my backyard. I raise them up so they don't get eaten by the fishies and release when they are frogs. I've done it before mutioke times with no issues. Some of my current batch seem to be displaying unusual behavior though. It's like they're chasing their own tail, but they don't seem to have very good control of themselves and it doesn't seem like they're doing it on purpose.
It almost reminds me of the way a poisoned snake I took in presented with a seizure.
They are less than 100 feet from the original pond, on my back porch with a bit of indirect sunlight filtering through. They were drip acclimated to conditioned tap water. They have a cycled sponge filter and live plants and rocks, algae and sand substrate (all also from the source pond, except the filter of course), and are cohabitating with a pair of pregnant ghost shrimp and some small snails (hitchhikers on the plants. Malaysian trumpet snails I think.)
The pond they come from does get pesticide and fertilizer run off from my neighbors, and they were collected very recently. Does anyone have experience with this kind of thing? Is there anything I can do besides provide them with clean water and appropriate food?
We are located in Melbourne FL.