If possible, find a slope under this hole and make a hole lower than the crack. If there is no hole with lower operating space, make this "broken" hole smoother first, and then do what you say.
The overhead way you do is desirable. It's not complicated Any brick will do. Simply fix it with water and sediment. Then you can put a red brick with a hole in the big break. As for how to say it, you can guarantee that if there is water, there will be water coming out. It's not too complicated You'll know later.
After finding the slope at the bottom of the pool, do a good job of waterproofing, and coat the bottom and edge of the pool more than twice. Put the ceramsite away, spread a layer of mortar directly, dry it and build bricks directly. Don't be waterproof any more! ! ! !
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