So I did a 50% water change in the 2 tanks today and swapped my 2 bettas an hour later. Fingers crossed it stops the tail biting as there's much more to watch in the kitchen, and stops the stress stripes as the bedroom is much quieter 




Our little friend Peacock Will Eventully get better
( getting one for free 
This one's Lotus, the tail biter. Peacock, the stress stripe is in Lotus' old tank and seems OK, but can still see the stripe.
The tank Lotus is in now is about 21l, with a good layer of sand, so maybe 19l water. He's acting like he's terrified, hiding away, pectoral fins going like the clappers. He's feeding fine though. The only smaller 'tank' I have is a 3 gall bowl I've just taken a betta out of as I couldn't find a suitable heater for it. My house is freezing, so that's a no go really.
I don't know whether moving him again this weekend would be too much stress and upheaval?
On the plus side, Rufus, my red veiltail from work, is well happy in his new 5 gall with some shrimp and is bubble nesting like a good 'un![]()
Or at least from my experience. XDnot all bettas will be happy in 5gals its actually honestly to much space