My parents have a pool that needs water filled every once in awhile manually using its controls to push water from the spa to the pool and vice versa. What if you could build a device that does it automatically for $15?
This could be great for those days you leave the house for a month vacation and more.
This device will automatically add water to your pool when it gets below a specified level. It does this all for under $15. By having a device fill the pool to a specific level, you can avoid wasting water by overfilling.

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