Repair of leak in koi pond

Pensacola FL

Description

If anyone out there has any knowledge of koi ponds and can figure out why the water is going down even after all the rain would be great. My son took the motor out and cleaned the box that was clogged up fixed the problem but he cannot do it with his back problem. I hate to see the koi die if this can be fixed. Maybe all the roots from the plants is causing it too because I have seen that happen. Let me know if you can do this and what you would charge to repair the problem. Thank you!