I've had a few random losses in one of my shrimp tanks over the last few months. I've been finding a body in the neighborhood of every two weeks and even with a macro lens haven't been able to see anything out the ordinary -until today. I was removing guppy grass and duckweed and noticed a tangerine tiger with a milky section around the thorax. It appears to be a loose molt, as shell is just hanging on to the body. I've watched these molt before and they usually pop right out in a second's time.
I've moved this shrimp into quarantine but I feel sure he's a goner. In the meantime, unsure what to treat the main tank with or if I even should. I have a good bit of meds on hand owning a pet supply store, as well as some expired Baytril from my reptile days. I mention that because it's said to be a go-to on YouTube videos, or I can get a fresh (in date) supply by Tuesday if I order it soon.
Parameters are all where I want them and virtually identical to 7 other tanks with thriving Neo populations. pH 7.0, KH >3, GH 8, TDS within 10 of 140, temperature is 69F, no detectable nitrogen in any form. All tanks get 10% water changes weekly like clockwork. Change water is 50% remineralized RO/DI and 50% tap, degassed for 48 hours and siphoned in slowly via airline tubing. I'm near positive it's not maintenance/water quality related. The tank in question has a sponge filter and an airstone with an over sized air pump bordering on ridiculous (Whisper AP 300). Water surface rolls in these tanks on my shrimp rack, gas exchange/low O2 levels simply can not be an issue. Here's a photo of the tank (after removing a ton of guppy grass and floaters):
Shrimp are fed 3x weekly with Jake's complete veggie 2 days a week and Dennerle protein food once weekly. Once in a while I substitute one of these for other Om Nom foods for variety, but these two are my go-to's. I feel like the diet is pretty on point and no food is left uneaten. There haven't been many losses I've missed because there were only 38 shrimp in there to begin with and the numbers haven't diminished noticeably.
I'm assuming the dark area around the head are organs and food since these have been present on these tangerine tigers since day 1. This photo is from 8-22-19 and they've all had this coloration.
Moved the shrimp to quarantine and got better photos. Definitely has a molting issue, but unsure if bacterial disease is also present. I nudged several shrimp in this tank to the front glass and took macro photos and could see nothing out of the ordinary except for on this individual. Any advice appreciated.