low calcium levels

[nats]

I need some help please. I was doing my weekly water testing and my calcium levels have dropped down to 320 from 480 last week. I have a Red Sea Max 35 gallon. I do weekly water changes 15-20 % and use RO Di water. I am using instant ocean salt. The tank is three months old with two small clowns a frogspawn and 4 little zoa frags. Alk is low too. I was thinking of buying c-balance 1 & 2
Just wondering would this product or something simular help increase calcium levels or is it only going to help maintain calcium.
Thank you

[fencer]

Something easy...like Argmilk or any other calcium supplement off the shelf. Since your system is small it is very likely this is a better way than to dose with Calcium chloride.

[purplepolypeater]

try a different test kit calcium test kits can oxidize take a saltwater sample to the lfs. that is a lot of calcium lost to virtually no coral was that after your weekly water change. is it a new bucket.

[sphelps]

Check you magnesium, when it's low it's very hard to maintain calcium levels. Also IO salt will have low calcium and alkalinity when mixed with RO water, it's made to work best with plain old tap water. In addition when only mixing up small amounts of salt you'll get different results every time, one time you might scoop up a lot of calcium, other times hardly any. Ideally you want to mix a full bag or pail at once but obviously that's not always practical. Any two part additive will work fine, they're all pretty much the same, you can also make your own if you're interested.

[mark]

find IO low in Ca right from the bucket (see here).

With the amounts it mixes out to, doing a water change without supplementing the Ca first, could see it causing a drop. Plus with the Mg low, hard to get the Ca up in the first place.

Personally I find it's not a problem now that I'm aware. Supplementing with bulk, Mg and Ca is still cost effective.