That makes more sense, maybe your right...
Negative on the seramis, never been a fan of clay for hydro...
That might explain the problem, are you growing the plant hydroponically?
If not then I'd guess a change out to rich well draining soil would help a lot!
It is very possible to grow alocasia in hydro, colocasia go ballistic! But it's a lot of work, water and feeding unless it's automated.
I've had some fun results with passive, bucket in bucket systems, you can even forgo the inner bucket,, just fill one bucket with medium with a hole drilled a few inches up the side, they'll drink it down fast but a new leaf per day is doable with the right colocasia.
