Tetra With New Lesions

As per thread https://forums.thinkfish.co.uk/fish-health/tetra-with-unhealed-injury, it turns out that the tetra with the relatively-well-healed injury has acquired a new overnight lesion/injury, having been perfectly fine yesterday.

I noticed what looked like a reddened, grazed area around her gill / base of her pectoral fin on her RHS (as opposed to the LHS flank where the longstanding other-but-healing injury was/is) this morning but couldn't quite identify the exact location as she insisted on keeping that side hidden from me. As the day has worn on, this seems to have additionally developed into a chunk of flesh lifted up from the body, almost resembling another gill in appearance due to the gap between body and flesh, and which looked at first as though it had a white lump on it but this seems to have disappeared. I caught her swimming down to a piece of bogwood and brushing the grazed/wounded area on that, as though using it to alleviate it a scratch - and I noticed that the piece of bogwood may be a bit rough so may be a cause of / have worsened whatever it is. Photos have not been possible but I'll put a food tablet in as that should help capture her and the new lesions on video.

Water quality all fine pre- and post- yesterday's weekly water change - but will update with specifics and video footage as soon as I'm able to.

I removed the wood to examine what I thought was a rough bit - it turned out to be soft but I removed it anyway. It does look as though it's an injury of some sort, though. I've sat for ages and ages by the tank but she is refusing to reveal the 'new' wounded side for more than a split second - I'll persevere, though. No-one is picking on her, although she seems to be remaining confined to the one position under the bogwood, whereas the others are more out in the open although her female friend and one of the males take it in turns to sit beside her (by her RHS).

Water readings are 0 ammonia, 0 nitrite, ~ or <25 nitrate, with pre- water change readings much the same (maybe slightly higher nitrate). I notice ammonium/NH4 from the tap these days is 0.1 or 0.2 but Seachem Prime rectifies this immediately to <0.05 (lowest reading on the JBL test).

The injury looks less raw/aggravated today so will hopefully clear up in a few days' time, thank goodness. Edited to add: the red, grazed area seems to have subsided, just leaving what looks like a puncture mark which will hopefully settle.

I wonder if it is just this fish's temperament which makes her go off by herself into places other fish won't go 

I think you're probably right there, Sue - and the two female tetras tend to go to a great deal of effort to be able to retrieve uneaten food morsels for eating (as well as snail poo ). The other one seems more robust and gets through more situations unscathed, while this one seems more injury prone despite being less risky - in fact, she seems to take after her owner. 

The new injury waxed and waned, subsiding to a dark bruise only, then worsening to the re-appearance of the lesion with a white fleck in it in lieu of where the scales were. The nearby gill started to look slightly inflamed too. Rather than adopt a "monitoring only" approach but with the lesion deepening further and further into the body over the course of time as per previous wound (which, ironically, continues to heal with signs of some scales starting to grow over it), I've gone straight to "medicate in the hospital tank" this time round, which commenced this evening.

Fingers crossed. 

Wishing her a rapid recovery.

As an update, I administered an additional two days' treatment (complete course plus additional treatment at the higher dosage, given my soft water) and decided today that I had really taken the situation as far as I could in attempting to help. Therefore, earlier in the day, I did two large water changes of the hospital tank to dilute the eSHa 2000 and added carbon to the filter to further assist, and have just transferred her back to the main tank. I think transferring her back is the best all round for everyone - her tail brightened up immediately from pale > bright red, the other tetras have welcomed her back by swishing their tails over her, while even the harlequins are leaving her in peace - I realised I'd transferred her just as one of the harlequins was in the midst of his daily afternoon antics of taking complete possession of the centre of the tank and chasing everyone away but he seems to have abandoned that in favour of letting her settle back in (intentionally or otherwise). Her RHS still looks badly bruised, and the back of her gill may be slightly inflamed, but otherwise the infected area seems to have settled.

I'm still at a loss as to what has caused this (eg heater burn even although only at 24'C, attempting to get through a slat in the plastic plant pots even although only bruised on one side and not at the widest point of her body, chased and potentially bitten by a shoalmate) and am not convinced of her long-term health but I'll continue to monitor the situation as usual.

I'm beginning to wonder if this particular fish has something systemic going on - or, at the very least, a proneness to wounds. The original wound is much better than it was (now very superficial with scales growing back) and the second wound has healed very well too (now looks much like a couple of dark marks similar to the dark marking on x-ray tetras near their gill). However...

I've just been feeding the fish and she wasn't interested but, instead, didn't move from her location where she was uncharacteristically hanging mid-tank, nose down. I think she's constipated and, indeed, there's a poo half-in, half-out. (Hope no-one's reading this while preparing/eating dinner.) However, the entire anal area is black, as though this is a 3rd wound which has developed. Whatever next?!

The half-in, half-out poo is red but the anal area is dark (black or dark red, depending on what angle it is viewed from). I think that's what alarmed me - it reminded me of what I'd seen in my pygmy cories a few years ago.

Fingers crossed for your tetra.
I hope you manage to get her to eat something that will help her situation.