Hi there, firstly, good idea, I have played around with this kind of deck before, I called it Frostbite Borealis.
You only want 30 cards. More than that and you risk not drawing your precious SoP. Patient decks can easilly get to their win condition before running out of cards.
Purify is an unnecessary card, most poison decks are too slow when you have healing too. Congeal is only useful if you face other cc creatures and need to fight for the supremacy of your squids. Dessication again in most games wouldnt be needed. Mirror shield is hardly ever useful, take 1 if you really fear ug or firebolt, but youll outrush fiirebolt probably anyway at 30 cards.
Im not at my PC so cant post codes, but i suggest either:
6 rol, 6 squid, 4 SoP, 4 sanc, 2 miracle, 8 water quanta, light mark.
Or:
6 rol, 6 squid, 4 Sop, 4 sanc, 2 deflagration, 8 water quanta, fire mark.