Hello everyone, this is my first post so go easy on me.

I have a standard 20 gallon shrimp only tank which is stocked with about 50 or so adults and young. I noticed one of them had a parasite on their rostrum, looked like scutariella. I removed the shrimp and gave it a salt dip. Then placed it in a 1 gallon hospital tank so I could have a chance at collecting the infected molts.

Anyway, it's been really hot so I left a fan on in the shrimp room and over night a bit of almond leaf fell into the tank. I think it was blown off the shelf next to the tank. When I check on the shrimp the next morning he looks nearly dead, passed out on his side. When I net the little guy he starts twitching and trying to move so I quickly move him to a container of water from the 20 gallon. He sinks to the bottom and occasionally flutters his pleopods. After reading a couple accounts of saving fish with ph shock I decide to net him and place him near the spray bar in the 20 gallon. Basically rigged the net to keep him in a highly oxygenated area of the tank but still separate from the other shrimp.

It's been a full 24 hours like this and he is still on his side or on his back. If I try to pick him up he bolts away, flutters his pleopods and wiggles his legs. Sometimes he stands up for a moment but ultimately he falls over and goes back to looking unconscious.

I have an assassin snail that would love to make his acquaintance but I don't want to kill him if he's got a chance at survival. Has anyone experienced anything like this before? Should I just cut my losses here? 

Sorry, this is a long post. I've been researching online to see if I could find any info on something like this happening but haven't found much.

TLDR: Shrimp in hospital tank got PH shock after almond leaf falls into tank. Placed shrimp in highly oxygenated area of shrimp tank. Shrimp looks dead until I try to pick him up, then goes back to looking dead.

You haven't told us what type of shrimp and what the difference in pH is.

They're red cherry shrimp.

The 20 gallon tank PH is 7.6

I'm not sure what the hospital tank PH was. I ended up tossing the water so I could quarantine a couple other scutariella infected shrimp.

Why do you say it is pH shock in that case, if you didn't know what the hospital tank's pH was? In my experience, it takes like a week to change the pH by .1 using IAL in my 5 gallon tank. Sorry if I'm a bit skeptical. Just thinking it could just be just sick because of the scutariella infection?  

Also I don't think the almond leaf would cause a change PH quick enough to cause a PH shock. So probably something else?

You're right, I'm assuming it's PH shock. When I checked the tank the water was extremely dark with tannins and from what I can tell the only thing that could have changed the parameters in the hospital tank was the almond leaf. The KH in my tank hovers around 2-3. Which is on the low side from what I understand. So I imagine the swing could have occurred pretty rapidly once the tanic acids depleted the KH buffer.

I buy the leaves at a LFS that I have bought from before so I dont think it was contaminated with anything.

The scutariella infection was pretty minor, only one wriggling parasite on it's rostrum. I've done salt dips before and used the same salt I'd used before with no negative results.

If it's not PH shock I'm kind of baffled as to what it could be.

You mentioned that it was very hot, was there a temperature difference between the hospital tank and the 20g?

Not really, thermometer read the same in each, about 78F.

Anyway, I have an update. The shrimp in question is dead. When I went to check on him he was no longer moving at all and his flesh had turned white.

Thanks for the responses. 

Ah sorry to hear that. I guess in future you can put a lid on the hospital tank and hope that a leaf doesn't feel like participating in a trick shot with the wind ?