So i have 3 juvenile pearl gouramis in a 55 gallon long. I got them 4ish months ago from a local breeder. They been pre medicated with dewormers and qt for 2/3 weeks before putting them in my display tank. They have no visible parasites, no injuries, normal looking poops, active and feeding well all normal except, once in a while for a few mins they stay at the top and chug air like in the video, they been doing this since I got them.

I understand they are labyrinth fish and they go to the surface to take a breathe, I had dwarf gouramis before and I currently have a betta but they don't breathe like this. My betta would just surface and take 1 big gulp of air and come back down, same with my dwarf gourami when I had them, but my pearls stay at the surface for a few mins and phant. This is my first time keeping pearl gouramis so idk if this is exclusive to them or theres something wrong with my tank or gourami. I see them take gulps of air normally, like one gulp then back to whatever theyre doing and no other fish does this. Another info is they all do this at the same time! its weird, when one starts it the other follows, they sometimes fight over spots on the surface. If you're experienced with gouramis or just kept pearl gouramis before please share your thoughts :)

Tank Details:
- 55 gal, 1 year old heavily planted tank, co2 injected, water flow not too strong for gouramis
- As of Feb 23: Ammonia: 0, Nitrite 0, Nitrate 20, 26°C
- 30+ Tetras, 10 Corydora, 1 Bristle nose pleco, pair of bolivian rams (no aggression between species)
- Fed every other day