Betta with sudden head swelling

Question
Normally my fish is very active and loves exploring his (eclipse hex 5, planted) tank, and was doing so yesterday until I introduced a bamboo shrimp to his home. The bamboo shrimp and the ghost shrimp he lives with are fine, and I do not know if the incidents are connected. However, a couple hours later he was extremely lethargic, though was never stress striped or pale colored during this period.

When I found him this morning his eyes were sort of sunken into his head, way more than is usual, and he was sitting on his side along the tank bottom. I tapped him and he was able to swim to the top, but I scooped him out anyway and put him into a more shallow container (with new preheated/treated water of the same temperature) and a small bubbler. Readings from a water testing kit put everything in normal parameters. I use aquarium salt and dechlorinator with regular partial water changes. I don't know what could have caused this, but his head and mouth definitely seem swollen, the rest of his body is not, and there is no pineconing to suggest dropsy, nor abnormal patches or discoloration. I've added some epsom salts to try to reduce the swelling, but it's too soon to tell if it's begun to work. At times he tries to skim across the top of the water with his mouth as if he's trying to gulp air, but can't. He also did not eat this morning. Thanks for your time, I hope you can help me. I love this fish. :(

Answer
Hi Rachel

I've said this many times on this forum....Shrimp, Snails and other such invertebrate creatures do not belong in an aquarium with beautiful Tropicals.

Now to help your Betta
Regardless of a sickness or not with every water change you want to add 1 teaspoon per gallon of aquarium salt in your tank. These things are hard to diagnose over the internet and I rarely try. Most likely some type of bacterial infection, poor water quality, an allergic reaction (yes fish get those) perhaps he hurt himself on a tank decoration. I don't think it is pop eye as I haven't heard of pop eye affecting the mouth.

Make sure when doing you weekly water changes your also suctioning the gravel with a gravelvac removing all the left over foods, waste, etc on the bottom of your tank.

Types of medications I recommend are Maracyn, Bettafix, and Melafix. Remember when medicating with any type of medication, it reduces the oxygen level in your water, so providing a airstone or another med called Mythelene Blue will help in reducing the stress of the lack of oxygen and the stress of medicating. Loss of oxygen isn't as big an issue with Bettas as it is with other Tropicals since Betta get oxygen from the air, not the water. Mythelene Blue is actually a medication that helps with your bettas respiratory system, so consider it.

Also remember most fish medications contain copper which is toxic to invertebrates like shrimp and will kill them.

Hope this helps you and your little guy gets better soon!