| | Re: B. japonica and Bleach
Yes! It is somewhat delicate- especially near the roots. So what I did when I had algae on mine was fill a lipped bowl with 2% bleach solution and try to just dip the leaves in it, laying the roots over the lip as best you can.
Leave it for 2 minutes. Set a timer- it's worth the couple seconds!
Blyxa looks like spaghetti when the leaves are killed. If this still toasts the blyxa after replanting (and I can't promise it won't), let the root balls stay in the soil- it'll grow back eventually.
If the roots weren't so great to begin with (not many, that is), float what's left in the tank- I recommend in a mesh bag or nylon stocking. They'll grow new leaves (albeit in the wrong direction). Then replant.
ALSO- if all this scares you (and I wouldn't blame you if this was too risky sounding) try hydrogen peroxide spot-treating. Get a dental syringe, fill with H2O2, turn off the filter, squirt- wait an hour- turn the filter back on. It's important that the light is on and watch for bubbling- this is good. Then do a water change.
Good luck! I've done it a bunch and I still have blyxa (even after "killing" it a couple times).