Tetra EasyStrips 6-in-1 Pond Test Strips · 25 strips is a Tetra-branded product in the ownkoi catalog. Six-in-one pond test strips from Tetra. Tests pH, alkalinity, carbonate hardness, nitrate, nitrite, and chlorine in a single dip. Specifications and pricing reflect the manufacturer-published or retailer-published data at the most recent catalog refresh. Verify the live listing on the source retailer page before purchase.