pea puffers swimming oddly

[Opie3001]

I have a 55 gal tank, heavily planted (lots of hiding places), CO2, High light, one HOB and 2 sponge air powered filters. It has two older pea puffers that are just fine and have been in there for months. Also I have ghost shrimp in there.

• pH = 7.6
• Nitrates = 0
• Hardness = Not sure but it is hard. Well water.
• Nitrite = 0
• Ammonia = 0
• KH/Buffer = Not sure
• Water Temperature = 75 to 78ish

Wife wanted to add more puffers. So she bought 3 that seemed strong and ok. Took my time putting them in the tank. 

Put them in a bowl and added a bit of tank water a little at a time for over an hour. Made sure the temp was the same.

One was swimming strong then just floated up to the top and died. I watch him do it. Seemed to be swimming strong and was covering the whole tank then just stopped and started floating to the top. 

For a few mins all 3 new ones were at the top and seemed to be gulping for air but then the other to were fine.

The 2nd one 4 days later (Today) started swimming in loops like a drunken sailor. I found him laying on the bottom in some dwarf hair grass. I thought he was dead but got near him he took off but then started looping around and floating about. He would dart sometimes but for the most part seems to be floating not swimming. He is still alive (I think they blend in great in this tank) but he sure is not acting right and I am worried about the little guy.

The 3rd seems ok right now.

This is not the first time we have had issues with Puffers doing the odd swimming loopy thing and they normally just die but I want to know what is making them do this. 

Love pea puffers and I built this big tank with them in mind. The two bigger ones hide a lot but seem to like it. It is packed with snails.

Anyone have any clue what I could have wrong? Is there anything I could do to help the little guy. 

[Colu]

There's a couple of things it could be they could have trapped air if they puffed up while you lifted them out of the water when transferring to the other tank  or it could be internal parasites with the odd swimming behaviour if it's internal parasites I would treat with Fritz expel p active ingredient is levamisole 

Edited October 25, 2021 by Colu

[Odd Duck]

Could it be too much CO2?  That’s the only thing that sounds likely to me and gasping at the top should always be taken as a “not enough oxygen” sign.  It could also be anything that causes gill damage since that also equals not enough oxygen.  It sounds like you have enough water circulation with an HOB plus sponges, so is there any chance of an anaerobic pocket being released?  Any odor to the tank?

[Guppysnail]

Let me start by I have never owned puffers. The drunken loop swimming instantly sounded like a fish with ammonia poisoning just from my personal experience.  Ammonia poisoning can show days to a week or more after the poisoning event. The stress of relocation could have been the proverbial straw that broke the camels back. @Odd Duck & @Colu does this maybe sound plausible for a puffer the way I have seen it hit other fish?

[Odd Duck]

On 10/25/2021 at 8:08 PM, Guppysnail said:

Let me start by I have never owned puffers. The drunken loop swimming instantly sounded like a fish with ammonia poisoning just from my personal experience.  Ammonia poisoning can show days to a week or more after the poisoning event. The stress of relocation could have been the proverbial straw that broke the camels back. @Odd Duck & @Colu does this maybe sound plausible for a puffer the way I have seen it hit other fish?

Yes.  Ammonia burn, or any other kind of chemical burn, is one of the things that can cause gill damage and reduced oxygen to the fish’s brain.

[Opie3001]

I checked the CO2 and turned it down a bit. The other tiny puffer and the two big ones seem ok when I can find them. They tend to hid in the plants alot.

Only the baby puffers were gulping at the top and then only for a few mins.

No smell to the tank. 

I cannot find the sick one this morning but I will keep looking.

Thank you guys for your help.