I cannot answer that. If he's rational but has bad info, correct him.

Ultra bleach is 6% Sodium Hypochlorite. Frequently, pool store "Liquid Chlorine" is also 6% Sodium Hypochlorite--EXACTLY the same stuff. "Liquid Shock" is usually 12.5% or 10% Sodium Hypochlorite. Show him that and explain that the "inert ingredients" in both is merely salt-water. Same stuff, different package.

There is NOTHING that "protects" the liner in tablets. In fact, they are MORE dangerous to the liner because they are EXTREMELY acidic, unlike bleach which is a base.

What they have is stabilizer (CYA--Cyanuric Acid) which stabilizes chlorine--slows its breakdown. You can add stabilizer seperately--not a bad thing.

Of course if your husband is the type for whom "My mind's made up, don't confuse me with FACTS!" you are done for. Then your problem isn't the pool......