Calcium and Alk

[unclesalty663]

I just setup up my 180 tank with live rock, sump, and protein skimmer. Have 2 clowns and 1 yellow tang moved from another tank. Ammonia-0 , Nitrite -0 , Nitrate -10. DID water Change after 30 days( 20%), Nitrate -5. My question is my Alk is 7 dKh, my calcium is 200, and magnesium is 1280, why is calcium and Alk so low?

 

[Salty1962]

Alk isn't bad not sure why Ca is low unless coralline has started growing. What salt are you using? What were your levels prior to WC? 20% won't change your levels that much on a 180. Some salt mixes are lower in levels of Alk and Ca.

 

[unclesalty663]

Using Reef Crystals, checked fresh saltwater mix, got 480 calcium and 11 dKh. Didn't check calcium and dkh before as all water in the tank was fresh saltwater. Could my live rock, which 80% had been bleached and recurred for 2 months be sucking up that much calcium? Or start of coralline algae?

 

[Randy Holmes-Farley]

I expect the calcium is a measurement error (quite common). There is no sink for it unless you have added massive amounts of alkalinity. It would take about 30 dKH of alkalinity to be added to drop calcium that much. Much less likely is a true bad starting batch of salt.

 

[unclesalty663]

Would you recommend massive water changes, calcium chloride supplements or both?

 

[unclesalty663]

^^^^ needed to add I used the same test kit to test a fresh saltwater mix, which read 480. Then used the same kit to retest the tank and again got 200.

 

[madweazl]

What is the salinity?

 

[unclesalty663]

1.025

 

[beaslbob]

^^^^ needed to add I used the same test kit to test a fresh saltwater mix, which read 480. Then used the same kit to retest the tank and again got 200.

I would use calcium chloride for calcium and baking soda for alk.

Reread the dr Randy Holmes-Farley diy improved two part method.

 

[madweazl]

Did the Ca precipitate?

 

[mcarroll]

Did the Ca precipitate?

It would take about 30 dKH of alkalinity to be added to drop calcium that much.

That's an "enhanced no". ;)

That's too weird....I'd be tempted to drain and start over. Seems like a waste at the same time, so not sure I'd do it though.

 

[unclesalty663]

I'm confused too. Going to do water changes and dose two part. Let you know what happens. Thanks!!!

 

[madweazl]

I'm confused too. Going to do water changes and dose two part. Let you know what happens. Thanks!!!

No sense in dosing the two part when all you need is the calcium; that will just compound the issue.

 

[unclesalty663]

I agree I'm only going to dose calcium to start! Thanks!

 

[madweazl]

I agree I'm only going to dose calcium to start! Thanks!

Do you have a LFS that you can take some water to just for a sanity check?

 

[unclesalty663]

Closest is 1 1/2 drive. Going to use a friends test kit to see if it's my test kit or a bad batch of salt.

 

[beaslbob]

FWIW calcium chloride is available from redimix concrete places. call around. and baking soda is available at any grocery store.

Just reread and follow tihe diy two part. The first part of that system is to do a one time correction to get things balanced out.

also have you tested magnesium? Could be the missing third part of the puzzle.

my .02

 

[unclesalty663]

@beaslbob. Mag was 1280. Other test kit also showed 200 calcium, 480 on fresh saltwater mix. Understand the fresh saltwater mix did use a different batch of salt. Believe bad batch of salt is the culprit of my current situation.

 

[beaslbob]

@beaslbob. Mag was 1280. Other test kit also showed 200 calcium, 480 on fresh saltwater mix. Understand the fresh saltwater mix did use a different batch of salt. Believe bad batch of salt is the culprit of my current situation.

could be.

still you got a tank with lowe calcium. So use the calcium chloride to get calcium up to ~400 or so and magnesium sulfate (Epsom salts) and magnesium chloride to get magnesium up to 1350 or so. My magnesium was 700-800 on my old 55g and it took literally an 5 pound bad of Epsom salts to get it up to 1300+. No adverse side effects.

Once that set of initial condition are met then the diy two part is just measuring alk and adding some when it drops. the adding some magnesium when you use up a gallon of the calcium and alk doses.

I got cal chlor (anhydrous 94%-96%) from a local redimix company. 25 pound bag was $8. or so. Plus they felt sorry for me and gave me a bag. LOL. I also got magnesium chloride and calciujm chloride from a local industrial supplier. First two 2 50 pound bags were about $30 total.

then I had so much I starting giving it away ag frag swaps and local club meeting LOL.

My .02

 

[unclesalty663]

Thanks I appreciate the help!