Issues with calcium

awais98 · Dec 18, 2017

Hi everyone
So I have my 240 DT system running about a year now.
Running basic zeovit.... ULNS.... feed fishes heavy.
Continuous water change .... 5 ml/ min
Instant ocean salt
Mainly acros..... majority growing ok .... ranges from few growing like 5x to others barely grown 20%, no death. Good pe

My ‘issues’:
1: Almost none coralline
2: On off cyano..... bubbly slime on heavy flow areas
3: My calcium keeps rising slowly over the year... see graph below. It’s been 600 lately last 2 months.... what do I do to fix this?
Or do I even need to fix this?

Some other parameters:
Alk pretty stable between 8-9 over the year...
Nitrate almost always zero
Phos usually zero

I know for the corals to grow good.... they need NSW sea levels especially with ULNS.... and hence me using instant ocean
My cal reactor is also set low:
Output is about 30ml/ min& CO2 only 1 bubble per 10 seconds.... maintains CRx pH 6.5.....

See parameters:

Shigshwa · Dec 18, 2017

The coralline issue could be low magnesium. Yes, you do want lower alk with a ULNS, but calcium and magnesium should be around 420 and 1350PPM respectively. What does your freshly mixed salt water measure with calcium, alkalinity, and magnesium? I think IO salt has a lower mag content than other salts.

Randy Holmes-Farley · Dec 18, 2017

I suspect a test issue on calcium, if you have not dosed any. I don't see how it could get to 600 ppm using IO salt mix and a reactor.

The coralline issue may be excessively low nutrients.

awais98 · Dec 18, 2017

I’m using Salifert calcium testing. I’ll use a new kit I have and see

awais98 · Dec 19, 2017

So I checked with another brand new salifert calcium test kid
With both the kits same result: 600!!

I’m at a loss why.

Randy Holmes-Farley · Dec 19, 2017

Are you sure you are not reading the kit backwards? Some people have done that.

Make sure that a whole syringe of liquid titrant added to get to the color change yields a lot of calcium, not a little.

Armydogracing · Dec 19, 2017

When you say no coralline are you talking purple? There is other colors of coralline.

Do you have urchins?

jsker · Dec 19, 2017

What are you clean your test vials with after the test?

Hanna had a live chat last week, it was stated not use tap water to rinse with especially with calcium tests. It was suggested to use distilled or RO/DI to rinse with before testing.

WWIII · Dec 19, 2017

Did you ever use Kent Marine Salt? I see you were talking about it being on sale earlier this year. Higher calcium in that salt vs regular io

Randy Holmes-Farley · Dec 19, 2017

jsker said:
What are you clean your test vials with after the test?

Hanna had a live chat last week, it was stated not use tap water to rinse with especially with calcium tests. It was suggested to use distilled or RO/DI to rinse with before testing.

That same problem is not an issue with the Salifert kit.

The Hanna uses a tremendous multiplier on the blank value that must zero the machine absorbance. So even a little calcium in it (say, 1 ppm) subtracts out a lot of calcium from the sample result, making it lower than it should be.

A titration kit involves no such correction for a blank, and 1 ppm calcium in the vial at the start will still only show as 1 ppm (in this case, as an extra 1 ppm).

For a Salifert kit to be off by 50% (as might be the case for the OP) would mean that there was a lot of tank water in the tube before you added the actual water sample, say 1/2 of the sample volume you were adding.

awais98 · Dec 19, 2017

Randy Holmes-Farley said:
Are you sure you are not reading the kit backwards? Some people have done that.

Make sure that a whole syringe of liquid titrant added to get to the color change yields a lot of calcium, not a little.

I hear you

)) I made sure.
For 600 Ppm calcium, the whole 1 ml is used up(500ppm) plus some more....to get 600PPM

awais98 · Dec 19, 2017

Armydogracing said:
When you say no coralline are you talking purple? There is other colors of coralline.

Do you have urchins?

What little sliver I have, is purple.....

Urchins are in the Frag tank not in dt.... didn’t really need it.... tangs take good care of any gha...

awais98 · Dec 19, 2017

WWIII said:
Did you ever use Kent Marine Salt? I see you were talking about it being on sale earlier this year. Higher calcium in that salt vs regular io

Yes I have used Kent marine in the past.....
Was using it until about 4 months ago....
I change about 60G a month..... slow continuous.
The calcium graph if you see up... has been going up for past 2-3 months not before that.......

awais98 · Dec 19, 2017

jsker said:
What are you clean your test vials with after the test?

Hanna had a live chat last week, it was stated not use tap water to rinse with especially with calcium tests. It was suggested to use distilled or RO/DI to rinse with before testing.

After testing...I simply wash with tap water and pat is dry with a towel...
Before testing I always rinse with tank water couple times before collecting sample water..

Randy Holmes-Farley · Dec 19, 2017

Maybe it's left from the Kent.

Elevated calcium is not typically an emergency issue.
next time you mix some new salt water, try the kit on that and see what you get.

jsker · Dec 19, 2017

Randy Holmes-Farley said:
That same problem is not an issue with the Salifert kit.

The Hanna uses a tremendous multiplier on the blank value that must zero the machine absorbance. So even a little calcium in it (say, 1 ppm) subtracts out a lot of calcium from the sample result, making it lower than it should be.

A titration kit involves no such correction for a blank, and 1 ppm calcium in the vial at the start will still only show as 1 ppm (in this case, as an extra 1 ppm).

For a Salifert kit to be off by 50% (as might be the case for the OP) would mean that there was a lot of tank water in the tube before you added the actual water sample, say 1/2 of the sample volume you were adding.

It just a suggestion Randy

Randy Holmes-Farley · Dec 19, 2017

jsker said:
It just a suggestion Randy

Thanks for suggesting it.

I didn't mean to claim it wasn't a good suggestion. I just didn't want him to focus on it as a possibility with the Salifert kit.

jsker · Dec 19, 2017

awais98 said:
After testing...I simply wash with tap water and pat is dry with a towel...
Before testing I always rinse with tank water couple times before collecting sample water..

Looks as though you are doing things right.

With cleaning. I use the Hanna, and Aquaforest test kits and when I get a off reading I will test with both. I am very confident that @Randy Holmes-Farley and other will help you figure out why the calcium reading is testing high

awais98 · Jan 7, 2018

So I checked again in 3 weeks: exact same numbers:
Cal 600
Alk 8.345

I’ve been feeding heavily past few weeks.....
Re zeovit.... I’m only dosing Zeostart daily (carbon source) .... pretty-much stopped every other zeovit additive and in 3 weeks my Phos is 0.001 and nitrate is 0.2.......

Coral colors are more intense than usually Zeovit Colors ......
Corals growth is same.... decent.

But calcium remains