Update since Sunday, May 21st:
Monday, May 22nd:
He still had a swollen belly, plus a 3" (8cm) long poop hanging off him, as in this photo:
Changed 25% of the water, and then gave him second dose (2/3 dose) of Parasite Clear. Concerned about rising nitrite level (between 0.3 and 0.8 mg/L) (ammonia negligible, so tank must be cycling still....new filter a couple of weeks ago). In the evening, I did another 20% water change, since I felt the nitrite problem was more urgent than the skin problem. Gave him a slice of cucumber at night....looked uneaten in morning.
Tues. May 23rd:
He looked a little better, but nitrites still rising (about 1.6 mg/L), so did 25% water change, bringing it down to 0.6 mg/L. Fed him frozen peas (thawed, de-shelled, and squeezed), which he went bonkers over!
Wed. May 24th (now):
His belly is now flat, and there is normal-looking poop around the tank gravel. He posed for me, showing good finnage, but still with that pale area:
On closer examination, I saw a small (less than 1 mm) milky-coloured lump on his tail. Gentle stroking with a wet cotton swab did not remove it. I wonder what that is? Can you see it here, by the red arrow? It looks like there are 2 lumps in this photo, but I think that's just poor photography:
BTW, his behaviour seems fine. He's active (light or dark), eats anytime, doesn't rub, has erect fins, and comes to greet me (wants food! Just like my dog!).
One other thing about that pale area: It seems to almost disappear when he's going nuts on those peas, in the evening! I mean, he really goes nuts! He's totally focused on eating, and just lets the current move him off the bottom, and around the corner of the tank, and he even lets it push him upside down! As long has he's latched onto that pea, he doesn't care!! It's hilarious! The "Pleco Pea Ballet"!
