Do I need this stuff ???? i have an Inground Vinyl Pool thats 32 x 16
3 ft shallow end going to 8 ft deep end

pool store tells me i need it !!!! My ph is 7.4 Cl is 1.5 and 1.5 and my cya is 75

Alk is 120 -130


Is there a Substitute for this ...Thanks Im a New Poster and reading but usually just lurk



Balance Pak 300

Balance Pak 300 boosts Calcium Hardness to help prevent equipment corrosion, etching of plaster and wrinkling of liners.
What it does:

• Helps to prevent damage to your pool equipment, such as pumps and heaters.
• Helps to balance Calcium Hardness.
• Have your water tested by your BioGuard Authorized Dealer to determine your Calcium Hardness Level.