Error with userdata value?

Why isn't this working? I always get this error : attempt to perform arithmetic on field 'ImageColor3' (a userdata value)

I don't get it..?

color = script.Parent

while wait() do
	local i = 0
	repeat
		wait(0.2)
		i = i + 1
		script.Parent.ImageColor3 = script.Parent.ImageColor3 + Color3.new(0,0,0+i)
		if i == 10 then break end
	until i == 10
	wait()
	local ii = 10
	repeat
		wait(0.2)
		ii = ii - 1
		script.Parent.ImageColor3 = script.Parent.ImageColor3 + Color3.new(0,0,0+i)
		if ii == 0 then break end
	until ii == 0
end

You would need to add each individual parameter separately. Read over this wiki page to better understand it.