Drain seaweed well and roughly snip them shorter. In a big bowl, toss seaweed with calamansi juice, sugar and salt.
Meanwhile pound chilli and belacan together, then toss with the seaweed. Chill it in the fridge until it's time to serve. Taste the seaweed after 30 minutes, if it needs more flavour, adjust according to your preference. (This can be prepared the day before).
When it's time to serve, mix with the other ingredients and garnish with coriander.
Best served chilled.
Recipe by at https://justasdelish.com/eucheuma-seaweed-kerabu/