Re: Inherited a pond, trying to turn it into a pool!
I don't know about cleaning your DE filter element or what the procedure would be but be careful - don't just dump it on - wear gloves and safety glasses/goggles, stay upwind of the fumes, avoid splashing. Always Always Always put Acid into Water (A->W). NEVER put water into acid. Muriatic acid can hurt you.
That said, It is great for lowering pH (you don't need to now if your pH is still 7.4). I read a post somewhere here that suggested storing the bottle(s) in a 5 gallon plastic pail with lid fastened to contain any possible spill and store the pail (acid and all) in a cool place out of harms way. It's not a good idea to store it with other chemicals or near metal objects as the fumes can cause corrosion.
To put in in your pool (if you need to), wear gloves, eyewear, stay upwind, hold the bottle in the pool with the lid just out of the water, remove lid, pour acid into pool keeping opening as close to water as possible (to avoid splashing), replace cap, rinse the whole closed bottle (and anyhting else that touched the acid) in pool before removing.
12'x24' oval 7.7K gal AG vinyl pool; ; Hayward S270T sand filter; Hayward EcoStar SP3400VSP pump; hrs; K-2006; PF:16
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