Struggling with Hornwort — would appreciate advice

I want to be honest: I'm not getting great results with Hornwort and I'm not entirely sure why. root-eating by water lily aphids or china mark moth has been a recurring problem despite my attempts to address it. I've been focusing on planting in aquatic baskets with specialist pond compost based on everything I've read.

cooling visual effect and microclimate benefit in summer is there in glimpses, which tells me the plant has potential in my conditions. I have it in a natural wildlife pond with naturalistic marginal planting which might not be ideal. overwintering dormancy in the pond bed showed some improvement. Two stars for now — not the plant's fault, but not a success yet. I'll update if things improve.