Maybe get a hard plastic pond liner and a pond pump. You can treat it like a pool, which would work too, and periodically clean it. https://www.homedepot.com/

Maybe get a hard plastic pond liner and a pond pump. You can treat it like a pool, which would work too, and periodically clean it. https://www.homedepot.com/pep/MacCourt-Grand-Cayman-165-Gal-Preformed-Pond-Liner-LP7824/308771479?g_store=&source=shoppingads&locale=en-US&&mtc=SHOPPING-BF-CDP-GGL-D28I-028_026_PATIO_FURN-NA-NA-NA-SMART-NA-NA-NA-NA-NBR-NA-NA-NA-SMART_SHP&cm_mmc=SHOPPING-BF-CDP-GGL-D28I-028_026_PATIO_FURN-NA-NA-NA-SMART-NA-NA-NA-NA-NBR-NA-NA-NA-SMART_SHP-71700000090520809-58700007648833865-92700071653004558&gclid=Cj0KCQjwlemWBhDUARIsAFp1rLXFUX44r-dNyC3VGPG6hPTWlU4tO_BHbZAn2PxbRKKlxf9H_aZ1HDoaAnOhEALw_wcB&gclsrc=aw.ds https://www.homedepot.com/pep/MacCourt-Grand-Cayman-165-Gal-...