I don't think so, each time you do a water change you do alk swing.

It is much more stable to do less water changes and to dose every hour or every two hour.

There is no way doing water change without dosing will keep your level stable and unless you perfectly match your new water alkalinity (very difficult to do with a ULN) you will get swings. Unless your new salt has the same alkalinity as your tank, which is unlikely as most salt mix have high alkalinity.

I have large amount of corals and SPS in my tank and I do water change every month. I dose each day for alk and calcium and my levels are very stable day and night. I very rarely get RTN or STN. Think I had it twice in 3 years on newly introduced corals, never on older corals. I have a setosa that was in pretty bad shape when I got it from fragalot shipping and it is now all recovered after a week in my tank.

So until you do dose, you will never have a very stable tank and you will have lots of alk swings.

I don't claim not to have swings

I test water before and after and alk goes 6 to 7 which is a small swing. Rather than have a large swing of a biweekly WC
I use RB salt and alk is never very high with said salt
This is just temperat till I get reactor

Sounds fine to me. Lots of work, but still fine :)

Lol

I have a 30 gallon cube with nsw and a valve on bottom. Its not bad. Just take 5 gal out of DT and put 5 in

A swing of 1dKH every 3 days is quite a bit IMO.

The most you can increase alk that is safe is 1.4dKH per 24hrs.

Thanks for all the info folks :)