For a tank this size you could raise your alk with a commercial buffer/reef building product to the desired level. After this time, you will need to supplement your tank on a daily basis with a 2-part additive to maintain those levels (depending on the coral load of you tank you will need to supplement different amounts).

The other less time consuming method is to invest in a calcium reactor to maintain your levels alk and ca.

Agreed.

Weekly testing, and the use of a commercial buffer to raise it. If you're looking for a product name, one of my favourites is Seachem Reef Buffer 8.3 which helps keep a higher pH. If you have a fish only tank it isn't as important, but if you have corals you should try to keep your alkalinity within a 1 dKH (less than 20 ppm) swing, so this may require dosing more than once a week.

Agree with most of whats been said above,except for one thing....do not use sponge of any kind(unless you are prepared to clean it daily).

hey
 

forgot to mention thats the down fall with that is the upkeep i have crystal clear water but needs cleaning every second day but i think it is worth it good luck with the tank