Calcium rises by itself

[Kevin D]

Does anyone know what would cause my calcium to rise on its own? Could it be from the aragonite rock in my tank? Or maybe from my ro/di? My calcium is off the charts on both my salifert and Hanna test kits. For months I have been only dosing the alkalinity portion of B-ionic and my alkalinity drops daily but the calcium seems to go up. After two water changes the calcium dropped to about 500 on my Hanna kit. Always over the 500 max on my salifert kit. Then by the end of the week it’s over 600 again on my Hanna kit. I have to add about 30 ml a day of the alkalinity to keep it over 8. It’s 8.4 now. I have a 240 gallon tank with a 125 gallon sump. When I do a water change I only drain the sump. I use reef crystals salt. When I started the tank in January I was dosing both parts and realized the calcium was off the charts. Is it possible I still have a buildup of calcium from then? I’ve only done two water changes since January because my other parameters seem good. Thoughts? Could this be a false reading? My magnium is around 1300. Nitrates about 4 ppm, phosphates about 29 ppb. Temp 79. Salinity 35 ppt.

 

[Dr. Reef]

hanna cal checker if thats what you are using has known to have problems. i would check cal against some other kit. what saltmix are you using.

 

[Randy Holmes-Farley]

Are you adding anything else at all?

FWIW, your demand is very low, and when demand is low, very minor processes may begin to dominate the alkalinity.

30 mL of B-ionic alk part in estimated 340 gallons water volume is only adding 0.2 dKH per day. If all of that was used to make calcium, carbonate, you would only consume only about 1.3 ppm calcium per day.

There isn't really any way for only calcium to rise in a reef tank unless it is being added somehow.

Tap water can be a significant source, but RO/DI at 0-1 ppm TDS is not.

Aragonite cannot do it. Even if you did get it to dissolve, it adds a lot of alkalinity too.

"After two water changes the calcium dropped to about 500 on my Hanna kit. Always over the 500 max on my salifert kit. Then by the end of the week it’s over 600 again on my Hanna kit"

How big were these water changes? I'm concerned there may just be a large amount of variability in the calcium testing, and that is hiding the very low demand. To drop from 600 to 500 ppm using Reef Crystals would likely take two changes of more than 30% each.

In the end, however, the calcium value is not very important in this range and I wouldn't worry about it too much. I'd just keep monitoring it and unless it starts getting above 600 routinely. 500-550 ppm is fine.

 

[ajm83]

Are you dosing anything else at all? Thinking things like Purple-Up etc

 

[Kevin D]

The only other thing I have added, and I dose it once a month is Florida aqua farms Coraline stimulator and it does not contain calcium from what I understand, it’s for trance elements only.

 

[Dr. Reef]

The only other thing I have added, and I dose it once a month is Florida aqua farms Coraline stimulator and it does not contain calcium from what I understand, it’s for trance elements only.

that is your source of extra calcium. most of these products that promote coralline algae usually dont mention the ingredients in them but are most likely to be rich in calcium and mag along with trace elements and vitamins.

 

[Kevin D]

Are you adding anything else at all?

FWIW, your demand is very low, and when demand is low, very minor processes may begin to dominate the alkalinity.

30 mL of B-ionic alk part in estimated 340 gallons water volume is only adding 0.2 dKH per day. If all of that was used to make calcium, carbonate, you would only consume only about 1.3 ppm calcium per day.

There isn't really any way for only calcium to rise in a reef tank unless it is being added somehow.

Tap water can be a significant source, but RO/DI at 0-1 ppm TDS is not.

Aragonite cannot do it. Even if you did get it to dissolve, it adds a lot of alkalinity too.

"After two water changes the calcium dropped to about 500 on my Hanna kit. Always over the 500 max on my salifert kit. Then by the end of the week it’s over 600 again on my Hanna kit"

How big were these water changes? I'm concerned there may just be a large amount of variability in the calcium testing, and that is hiding the very low demand. To drop from 600 to 500 ppm using Reef Crystals would likely take two changes of more than 30% each.

In the end, however, the calcium value is not very important in this range and I wouldn't worry about it too much. I'd just keep monitoring it and unless it starts getting above 600 routinely. 500-550 ppm is fine.

The water changes are about a 100-110 gallons. I drain my sump and fill it for a water change. My RO/DI meter reads about 5-6 tds so kit sure that would make a huge difference. My demand it relately low for sure. I have about 40 corals in the tank, most frag size. My too largest are a frogspawn and a elegance but the elegance hasn’t been doing well. It won’t open fully so I wasn’t sure if this could be part of the reason. I just raised my nitrates from 1 ppm to 4-5 ppm in the last month and many of my LPS seem to have responded favorably. Some haven’t but they may too far gone already. To give you an idea, since January, I have doses about 1/4 gallon of the calcium part of the B-ionic. Is stopped all together in March. I am just about finished with a gallon of the alkalinity part. And I’ve done a total of about 300 gallons of water changes using reef crystals since January. My salifert kit doesn’t change color so it over 500. And the Hanna flashed 600 so I think that means over 600. I have run straight RO/DI throughbthe hanna and it reads 250 but to be honest I’m not sure that would read correctly since it’s not saltwater. Any thoughts on that? Maybe it’s my water? Does that seem high for city water run through an RO/DI? My resins shows it’s about 1/4 used and I’ve changed it once since January.

 

[Kevin D]

that is your source of extra calcium. most of these products that promote coralline algae usually dont mention the ingredients in them but are most likely to be rich in calcium and mag along with trace elements and vitamins.

This one lists the ingredients as chelates iron, iodide, trace metals, vitamins including B-12, botin, and thiamin. It’s advertised as a supplement of trace metals and vitamins. I can call them but I doubt it contains large amounts of calcium, if any. I’ve used this stuff for years. It’s the best.

 

[Kevin D]

I just retested with my salifert kit and it changed color on the last drop so that puts me at 500 for that kit. At least it changed color finally. The hanna reads 600. I thought Hanna’s were the best? For the money it ticks me off if that ones is so far off.

 

[Dr. Reef]

i did tell you hanna cal checker is not a reliable test in my first post. lol. they are known to have problems from the time they came out.
I am not a chemist but i am pretty sure ALL coralline products contain calcium.

 

[ajm83]

i did tell you hanna cal checker is not a reliable test in my first post. lol. they are known to have problems from the time they came out.
I am not a chemist but i am pretty sure ALL coralline products contain calcium.

Yeah exactly, that's why I mentioned 'Purple Up'.

I looked up the ingredients of that Coralline Stimulator product, and they mentioned strontium but not calcium. Guess that makes sense if it's intended to be used with a calcium-only 2-part.

Still wouldn't be surprised if that was the source though.

 

[Kevin D]

Well I will stop dosing it for a while to see if it makes a difference but I only dose about 25 mil of that a month, if that so I doubt that’s the source but I’ll try it and see. I have a feeling it may be my tap water and the RO/DI isn’t removing it all. Not that I have a color change on the salifert test, I can monitor it better.

 

[Randy Holmes-Farley]

My money is on the calcium “rise” being test measurement issues. I suspect it is just naturally high and stays high due to low demand.

 

[Kevin D]

That could very well be. That’s what the people that make B-Ionic said but what got me was that it tested lower the day after my water change and then a week later was back up but I guess if the Hanna tester is no good then that could explain it. I’ll keep an eye on it. Thanks for all the help and comments.

 

[Randy Holmes-Farley]

You're welcome.

let us know how things shake out over the coming weeks.

 

[Kevin D]

Will do.

 

[pdisner]

I believe that calcium can rise especially if something caused it to precipitate out of solution. But don’t trust fancy test kits when you’re talking fine tuning. I’ve definately had that happen on more than one occasion, just not drastically. I know that is a little ambiguous, but you will need to kind of play with it your self says every tank is a little different. Your best bet is to get a hold of one of a chemist who is s hobbyist. I know one who can help. Do u want his contact info? If so send me a pm. He can solve the riddle. But that’s my guess, you have something that’s causing Ca to precipitate out of solution. I’m not a biochemist though. Let me know if u want me to ask.

 

[Kevin D]

I think I’m good for now. The chemist idea is a good one and I work with a few so I can always talk them them if it gets too crazy. I don’t think the ca is precipitating out though or my levels would be low and I’m not seeing it precip out. I’m going to bring some of my RODI into work and runnit through the ICP. And I’ll stick to my salifert test kit for now and forget the hanna. I’ll let you guys know if anything changes in a few weeks. Thanks for the advice.

 

[Randy Holmes-Farley]

I believe that calcium can rise especially if something caused it to precipitate out of solution. But don’t trust fancy test kits when you’re talking fine tuning. I’ve definately had that happen on more than one occasion, just not drastically. I know that is a little ambiguous, but you will need to kind of play with it your self says every tank is a little different. Your best bet is to get a hold of one of a chemist who is s hobbyist. I know one who can help. Do u want his contact info? If so send me a pm. He can solve the riddle. But that’s my guess, you have something that’s causing Ca to precipitate out of solution. I’m not a biochemist though. Let me know if u want me to ask.

lol

I'm an chemist (PhD from Harvard, decades of reef chemistry experience...), and while precipitation of calcium carbonate can happen, it removes alk when it precipitates and it adds it back when it redissolves. So that is not the explanation. There is no other calcium material that is preciptiating and redissolving from a reef tank.

 

[Kevin D]

Yeah exactly, that's why I mentioned 'Purple Up'.

I looked up the ingredients of that Coralline Stimulator product, and they mentioned strontium but not calcium. Guess that makes sense if it's intended to be used with a calcium-only 2-part.

Still wouldn't be surprised if that was the source though.

Just an FYI, I spoke with Florida aqua farms and the Coraline stimulator does not contain calcium. So for those of you looking for a good supplement, I highly recommend it. I used in I’m my tank many years ago and it did wonders for my corals and Coraline. I used that and b-ionic exclusively and never had issues which is why I went back to it for this new tank. Just wish I could figure out what my issues are now. Maybe I’m just rushing things. Will keep you all posted on the calcium drop. On a side note it does appear that raising my nitrates to 4-5 ppm has helped my corals considerably.