Any way to LOWER alk in newly mixed salt water?

[Tigé21v]

Just curious.

[bertoni]

Adding a mineral acid will do the job. It's easy to overshoot, so I wouldn't add any to a running tank. Vinegar will reduce alkalinity very temporarily, until bacteria consume the organic acid.

[Tigé21v]

What mineral acid would you recommend?
I've been using Kent, but the alk is a little on the high side (dosing vodka).

[Randy Holmes-Farley]

I generally think it more trouble than it is worth, and the same effect can be accomplished just by adding a tiny bit less alkalinity each day, but muriatic acid (hydrochloric) would be the thing to use. Sulfuric is OK, but few people have access to it.

A 10% water change with 12 dKH seawater in an 8 dKH tank only boosts alkalinity to 8.4 dKH.

[beefcake78]

make sure you are starting with ro first, my tap has really high alk before I add salt