Maybe you burned the roots with too much fert. Don't fertilize unless really actively growing or rootbound.

I don't know about watering too little bring the culprit, but hmm, I have fed it quite a bit so I suppose that's could be it. Can it be salvaged? I'll try posting a pic. I couldn't figure out how when I posted the comment.

Thank you both for your advice.

Here's another shot

And a close up

Rina, I love your "fishbone" 👍

Margaret,

I would cut those green ends off your plant, let them callus for a day, and start them in a tray of good potting mix or perlite to get them rooted in. The rest of the plant looks like it needs to be tossed but maybe the plant would revive if cut back hard but I seriously doubt that. Get rid of the big rocks too as that may be rotting the stems near the ground which probably is what doomed the plant.

https://www.gardeningknowhow.com/ornamental/cacti-succulents/epiphyllum/epiphyllum-plant-care.htm

Looks overwatered with a lot of salt buildup in the soil. In spring I would repot in fresh soil, and include some Perlite and fir bark for drainage.

Margaret Smart

I would attempt to save & root some green tips, but they don't look that healthy. I don't know how often you watered it, but it was either over- or under-watered. And def overfertilized. I don't fertilize mine on purpose; they may receive some fert occasionaly if any left over from fertigating my veggies. In warm months only...Being epithypes, they should be potted in very well draining & chunky mix. I wouldn't use sand in the mix as recomended in the article linked...but that's me! I would rather add coarse perlite & bark (or cocochunks).

Thanks for the great advice, everyone. I cut off the green tips and will let them callus and I've rinsed the roots on the rest of the plants (get rid of excess salt?) and have replanted them in an orchid mix with a bit of bark thrown in. When the tips have callused I'l plant them in there too. Not sure if I should water the transplant now or wait a week or so ... I'll definitely hold off on fert! It's in an east facing window, is this ok? Not on the windowsill, just in front of the window

I usually don't water fresh transplants with roots for a day just to make sure any cuts have healed. You said you washed the roots & plants - maybe they were wet to water right away anyways? Only you know...Also, cutting without roots can't take in any water, so I don't water for a while. Some ppl spritz the soil around, I rather wait. No roots - no water...

I would be interested to know if any grow, since what I see in the photo doesn't look 'alive'. But let's hope so! Maybe they will; and hopefully some of the green pieces will start growing roots. Pls. follow up if possible.

Thank you rina, for the extra advice. I won't water the little leaf cuttings or the rest of the plant. I'd be amazed if this poor thing revives. I will definitely follow up in a few weeks! Thanks again for your help and interest!