In order to do the Health potion re-fill formula, you go to Warlic's shop and click explore, then sure thing, really.

1. Click,Drag Mermazon Kelp drag it into te bowl DIRECTLY south of the kelp.(not South-west)

2. Then Click,Drag Frogzards Tear into the same Bowl.(next to the ,Right bottle)

3. Then Click, Drag Magma Leaf (red Coral looking)

Then your potions will be restored to an amount.

Hope this Helps ^^