minetest.register_node(
    "portalgun:toxwater_1",
    {
        description = "Toxic water",
        drawtype = "liquid",
        tiles = {"portalgun_toxwat.png"},
        alpha = 190,
        paramtype = "light",
        walkable = false,
        pointable = false,
        diggable = false,
        buildable_to = true,
        is_ground_content = false,
        drop = "",
        drowning = 1,
        damage_per_second = 20,
        liquidtype = "source",
        liquid_alternative_flowing = "portalgun:toxwater_2",
        liquid_alternative_source = "portalgun:toxwater_1",
        liquid_viscosity = 2,
        liquid_renewable = false,
        liquid_range = 3,
        post_effect_color = {a = 200, r = 119, g = 70, b = 16},
        groups = {water = 3, liquid = 3}
    }
)

minetest.register_node(
    "portalgun:toxwater_2",
    {
        description = "Toxic water 2",
        drawtype = "flowingliquid",
        tiles = {name = "portalgun_toxwat.png", backface_culling = false},
        special_tiles = {
            {name = "portalgun_toxwat.png", backface_culling = true},
            {name = "portalgun_toxwat.png", backface_culling = false}
        },
        alpha = 190,
        paramtype = "light",
        paramtype2 = "flowingliquid",
        walkable = false,
        pointable = false,
        diggable = false,
        buildable_to = true,
        is_ground_content = false,
        drop = "",
        drowning = 1,
        damage_per_second = 4,
        liquidtype = "flowing",
        liquid_alternative_flowing = "portalgun:toxwater_2",
        liquid_alternative_source = "portalgun:toxwater_1",
        liquid_viscosity = 2,
        liquid_renewable = false,
        liquid_range = 3,
        post_effect_color = {a = 200, r = 119, g = 70, b = 16},
        groups = {water = 3, liquid = 3, not_in_creative_inventory = 1}
    }
)