Phosphate RX - Safety seal

[LittleMaui]

Hello, I ordered some Phosphate Rx online. I removed my GFO and added 1/2 the recommended dosage to drop my PO4 from 0.21 to 0.08, which would be 6 drops. I added the drops inside my skimmer body and added a felt filter to the sump. The next day I tested my PO4 and it went up a little, instead of down.

The top of the Phosphate Rx bottle looks a little odd and had no safety seal. How can I ensure the fluid inside the bottle hasn't been replaced with water?

shawn

 

[Randy Holmes-Farley Verified Community Expert]

A partial replacement would require an quantitative analysis such as icp to detect.

A complete replacement might be detected by mixing with phosphate-containing tank water and looking for a precipitate.