Hi, my fish have just undergone an incredibly stressful passing of one of their tankmates - and I was needing help on the cause of the death.
I have a 250 litre tank, well established.
Nitrate: 0.05ppm (if that)
: 0-5ppm (I am really unsure on how to boost this so perhaps it contributed?)
(Heavily planted, 20-25% water changes weekly, canister filter + heated tank)
I have 4 dwarf gourami, and although they have a fraught relationship from time to time, they're only defending their various nests. This particular dwarf gourami had been losing colour quickly, frequent issues with bloating, and black/discoloration on fins. Until today, he was active, swimming a lot, instead today he was sitting on the bottom of the tank, where I moved him to a quarantine tank and settled him in a net near the top of the water to be able to get oxygen.
He soon became entirely unresponsive, though still alive, so I quickly moved him to a container with clove bud oil, where he passed (however is still sitting in as a precaution).
I will attach some photos, and I hope you all might be able to aid in the identification/or even if this 'disease' or otherwise will be a threat to my other DG. (I'm new-ish to fish keeping, and as being 15 this is majorly stressful. Please attach any advice, I'd really appreciate it)