Roblox Studio Lua: Detecting with Water reduces Health. How to make it stop when out of water

I want to make an area in which you lose health, but once out, you don't. So i have created a part, made transparency to 1, and canCollide to false, than put it inside of water. In the code character loses health when enter water, but still lose when out. This is a code i have

local parent = script.Parent -- the part
local Player = game:GetService('Players')

local isInWater = false
local setHealth = 0

local function onCollide (hit)

    local character = hit.Parent
    local player = Player:GetPlayerFromCharacter(character)
    local humanoid = character:FindFirstChild('Humanoid')
    isInWater = true
    print('in water')

    if player and humanoid and isInWater then
        for initalHealth = humanoid.Health, setHealth, -10 do
            humanoid.Health = initalHealth
            task.wait(.2)
        end
    end
end

parent.Touched:Connect(onCollide)

parent.TouchEnded:Connect(function()
    isInWater = false
    print('left water')
    task.wait(1)
end)

I made a variable isInWater, which is set to false by default, but once you collide with parent it sets to true, in for loop it's mandatory to work with isInWater being set to true. Then came up with yet another function for TouchEnded event to set isInWater to false once you end touching the part. Now for loop should probably stop. Than i thought that for loop won't stop because loop have already begun the job. So what can i do? I'm new to Lua, so any help would be appreciated

Solution

Your onCollide function runs every time something enters the collision box of the transparent part, but the part of your code that is giving you problems is this:

isInWater = true -- this runs every time onCollide runs

What this is doing is that isInWater is being set to true every single time onCollide runs, when you should really check for the player before running your for-loop.

Then, inside of your for-loop, to check if the player is still in the water, you should insert:

if not isInWater then -- breaks the for loop when not in water
  break
end

before you decrement health.

Hope I helped!