Reef Central Online Community

Home Forum Here you can view your subscribed threads, work with private messages and edit your profile and preferences View New Posts View Today's Posts

Find other members Frequently Asked Questions Search Reefkeeping ...an online magazine for marine aquarists Support our sponsors and mention Reef Central

Go Back   Reef Central Online Community > General Interest Forums > The Reef Chemistry Forum
Register Blogs FAQ Calendar Mark Forums Read

Notices

User Tag List

Reply
Thread Tools
Old 05/18/2019, 05:11 AM   #1
dava6711
Registered Member
 
dava6711's Avatar
 
Join Date: Mar 2010
Location: England, UK
Posts: 140
Calcium & Alkalinity Issues

Hi

This is making me rip my hair out in frustration.

I have a reefer 170 tank, it’s stocked with a single Macrodactyla doreensis anemone, a selection of three small fish, royal gramma, clown fish & a bangaii cardinal & a selection of macroalgae.

The display tank is lit by a single 150w metal halide (20k bulb, on for 8 hours a day).

Biological filtration is accomplished by a fluidised sand filter in the sump.

Current parameters are:-
Calcium: 320ppm.
Alkalinity: 8dKH.
Magnesium: 1080ppm.
Nitrate: trace.
(I know that calcium & magnesium are too low).

My rate of alkalinity depletion is unreal, like 1dKH a day. In an attempt to maintain my alkalinity I’m using saturated calcium hydroxide for all top off water, this is only stopping the alkalinity from being depleted as fast, calcium hydroxide alone is unable to maintain, I’m having to supplement with sodium bicarbonate alongside the calcium hydroxide.

How can other aquarists maintain their large, fully fledged reef tanks calcium and alkalinity demands using calcium hydroxide, but I can't accomplish this on a reefer 170 (approximately 43 gallons) with no hard corals or live rock?

If my calcium was super saturated I understand I’d have difficulty raising the alkalinity as I’d have a precipitation event, but I'm able to raise the alkalinity easily with my calcium being so low, testing after adding sodium bicarbonate confirms the increase in alkalinity but it still gets depleted so quickly.

I have no live rock, and no hard coral. Just 3 small fish, an anemone (very healthy) and macroalgae, that’s it.

So how is it being depleted so fast with no live rock, and no hard corals (or even soft corals for that matter), just the anemone and three fish?

Any help will be greatly appreciated.



Last edited by dava6711; 05/18/2019 at 05:33 AM.
dava6711 is offline   Reply With Quote
Old 05/18/2019, 10:00 AM   #2
dubmaneh
Registered Member
 
Join Date: Sep 2012
Location: Toronto, ON
Posts: 203
You may be dosing too much alkalinity. IME dosing too much has the effect of actually lowering it because it will precipitate onto heaters, pumps etc.

How did you test your demand?


Sent from my iPhone using Tapatalk Pro


dubmaneh is offline   Reply With Quote
Old 05/18/2019, 11:59 AM   #3
dava6711
Registered Member
 
dava6711's Avatar
 
Join Date: Mar 2010
Location: England, UK
Posts: 140
[QUOTE=dubmaneh;25590045]You may be dosing too much alkalinity. IME dosing too much has the effect of actually lowering it because it will precipitate onto heaters, pumps etc.

How did you test your demand?

Confirmed the rate of depletion by daily testing, recording the results & observing weekly trends.


dava6711 is offline   Reply With Quote
Old 05/18/2019, 01:13 PM   #4
hegeh
Registered Member
 
Join Date: Apr 2017
Posts: 177
Less is more. Is your solution of ALk correct? I had the same issue previously. But i learned i was mixing the wrong ratio and caused the calcium to percipitate. They chase each other as i tries to bring up the calcium. Finally i settled with Aquaforest KH buffer when my previous of DIY alk solution used up. Lesson learned is i might have my calculation wrong or i bake my sodium bicarbonate wrongly.

Sent from my SM-G930F using Tapatalk


hegeh is offline   Reply With Quote
Old 05/18/2019, 06:34 PM   #5
bertoni
RC Mod
 
Join Date: Mar 2002
Location: Mountain View, CA, USA
Posts: 88,100
1 dKH per day along with Kalk topoff is credible. My soft coral tanks went through more than that due to coralline growth alone. How long has the the tank been running? Often, new sandbeds and rock seem to provide a lot of nucleation sites that encourage abiotic precipitation.


__________________
Jonathan Bertoni
bertoni is online now   Reply With Quote
Old 05/19/2019, 03:09 AM   #6
dava6711
Registered Member
 
dava6711's Avatar
 
Join Date: Mar 2010
Location: England, UK
Posts: 140
Quote:
Originally Posted by bertoni View Post
1 dKH per day along with Kalk topoff is credible. My soft coral tanks went through more than that due to coralline growth alone. How long has the the tank been running? Often, new sandbeds and rock seem to provide a lot of nucleation sites that encourage abiotic precipitation.
Interesting, Iíd never heard of that. Itís been running for around 6 months so your theory does sound like a possibility.

Iím gonna stop using Kalk and continue using bicarbonate & calcium chloride then as I donít like the mess the Kalk has been making in my sump.


dava6711 is offline   Reply With Quote
Old 05/19/2019, 05:20 PM   #7
bertoni
RC Mod
 
Join Date: Mar 2002
Location: Mountain View, CA, USA
Posts: 88,100
Maybe a fair amount of the Kalk is precipitating?


__________________
Jonathan Bertoni
bertoni is online now   Reply With Quote
Old 05/19/2019, 05:37 PM   #8
dava6711
Registered Member
 
dava6711's Avatar
 
Join Date: Mar 2010
Location: England, UK
Posts: 140
Quote:
Originally Posted by bertoni View Post
Maybe a fair amount of the Kalk is precipitating?
Only in the fresh water reservoir & on the float valve.

Note, I wasnít using kalk at first. Iíve only been using it about a month or so in an attempt to prevent my alkalinity swings. This has been an ongoing issue.

Iím gonna try leaving the alkalinity for a few days. Refrain from both testing & supplementing and observe the tank carefully, if I remember rightly it never seemed to drop below 7.7dKH.


dava6711 is offline   Reply With Quote
Old 05/19/2019, 07:35 PM   #9
bertoni
RC Mod
 
Join Date: Mar 2002
Location: Mountain View, CA, USA
Posts: 88,100
Okay, that seems reasonable. Good luck!


__________________
Jonathan Bertoni
bertoni is online now   Reply With Quote
Old 05/20/2019, 01:29 PM   #10
Uncle99
Crab Free Zone
 
Uncle99's Avatar
 
Join Date: Sep 2017
Location: Ontario, Canada
Posts: 2,787
I just don't understand why you dose anything if you have nothing that uses it?

Notwithstanding, your likely getting a false reading as your MG is too low.

Not that you need too but if you want to maintain Stoney coral water chemistry, I would increase your MG to 1260-1360 ppm, otherwise the Alk ion and the CA ion will come together to fast. Your a bit to low in my mind. MG purpose is to make both those calcification ions less attracted to each other and stay in the solution to be used by Stoneys.

Otherwise they just come together quickly and precipitate out leaving a low level when testing.



Last edited by Uncle99; 05/20/2019 at 01:43 PM.
Uncle99 is offline   Reply With Quote
Old 05/20/2019, 04:02 PM   #11
dava6711
Registered Member
 
dava6711's Avatar
 
Join Date: Mar 2010
Location: England, UK
Posts: 140
Quote:
Originally Posted by Uncle99 View Post
I just don't understand why you dose anything if you have nothing that uses it?

Notwithstanding, your likely getting a false reading as your MG is too low.

Not that you need too but if you want to maintain Stoney coral water chemistry, I would increase your MG to 1260-1360 ppm, otherwise the Alk ion and the CA ion will come together to fast. Your a bit to low in my mind. MG purpose is to make both those calcification ions less attracted to each other and stay in the solution to be used by Stoneys.

Otherwise they just come together quickly and precipitate out leaving a low level when testing.
Iím dosing to replicate their environmental conditions.

I realise my magnesium is low but never realised it was as important as it obviously is to manitain a stable calcium and alkalinity.

In order to get my magnesium to the ideal level, I need to dose approximately 450 grams, dosing that much absolutely canít be good for my water chemistry, itís surely gonna increase my salinity significantly! I guess I could increase it extremely gradually.


dava6711 is offline   Reply With Quote
Old 05/20/2019, 11:29 PM   #12
bertoni
RC Mod
 
Join Date: Mar 2002
Location: Mountain View, CA, USA
Posts: 88,100
Magnesium at 1080 ppm is a bit low, but not that bad. I ran tanks at that level for years because IO came at that level for a long time. The low magnesium level will not affect test kit results.


__________________
Jonathan Bertoni
bertoni is online now   Reply With Quote
Old 05/22/2019, 01:00 PM   #13
Uncle99
Crab Free Zone
 
Uncle99's Avatar
 
Join Date: Sep 2017
Location: Ontario, Canada
Posts: 2,787
Quote:
Originally Posted by dava6711 View Post
I’m dosing to replicate their environmental conditions.

I realise my magnesium is low but never realised it was as important as it obviously is to manitain a stable calcium and alkalinity.

In order to get my magnesium to the ideal level, I need to dose approximately 450 grams, dosing that much absolutely can’t be good for my water chemistry, it’s surely gonna increase my salinity significantly! I guess I could increase it extremely gradually.
I struggled with maintaining CA and Alk for quite some time until a member guided me on the keeping MG on point. Since I followed this direction, CA and Alk have been easy to maintain.

For me, anything below 1100 ppm seemed to bring varied testing results for Alk.

I maintain 1320-1360 ppm for 28 months now, and with hourly dosing of Alk, the flux is 10ppm at any time.

Slow increase.....absolutely....and that applies to everything.....say 20-30ppm every other day is fine.....

While levels are important.....consistency is everything


Uncle99 is offline   Reply With Quote
Old 05/22/2019, 02:53 PM   #14
hkgar
Registered Member
 
hkgar's Avatar
 
Join Date: Oct 2002
Location: Dewitt MI
Posts: 4,912
I would raise mag to at least 1250. I like to keep mine at 1400+


__________________
Gary


180 gallon, 30 gallon sump, 8 80W ATI T5's, MTC MVX 36 Skimmer, Apex controller Aquamaxx T-3 CaRx

Current Tank Info: 2 Barred Rabbitfish, Yellow/Purple, McMaster Fairy, Possum, 2 Leopard Wrasses, Kole, & Atlantic Blue Tangs, 2 Percula Clown, 4 PJ and 2 Banggai Cardinalfish , Swallowtail and Bellus, Flame, Coral Beauty Angels
hkgar is offline   Reply With Quote
Old 06/13/2019, 03:54 PM   #15
dava6711
Registered Member
 
dava6711's Avatar
 
Join Date: Mar 2010
Location: England, UK
Posts: 140
Update

After slowly increasing magnesium to 1320mg/L using magnesium chloride, and calcium to 420ppm using anhydrous calcium chloride my alkalinity has remained rock solid at 8.3dKH.

So it appears that all the suggestions on this thread recommending I increase magnesium were indeed correct.

My parameters have been absolutely rock solid & stable.

Nitrate: trace.
Magnesium: 1320mg/L.
Calcium: 420ppm.
Alkalinity: 8.3dKH.

I want to thank all the members who posted in this thread.



Last edited by dava6711; 06/13/2019 at 04:24 PM.
dava6711 is offline   Reply With Quote
Old 06/14/2019, 12:55 PM   #16
Uncle99
Crab Free Zone
 
Uncle99's Avatar
 
Join Date: Sep 2017
Location: Ontario, Canada
Posts: 2,787
And that is excellent news!
Thanks for keeping us in the loop.


Uncle99 is offline   Reply With Quote
Old 06/14/2019, 02:43 PM   #17
dava6711
Registered Member
 
dava6711's Avatar
 
Join Date: Mar 2010
Location: England, UK
Posts: 140
Quote:
Originally Posted by Uncle99 View Post
And that is excellent news!
Thanks for keeping us in the loop.
Thatís why I updated, Iíve seen so many threads created with no updates or any sign of closure from the OP.

Iím slightly embarrassed that I had to create a thread about my issues maintaining a stable alkalinity when the resolution was so simple!


dava6711 is offline   Reply With Quote
Old 06/22/2019, 09:29 PM   #18
TwoShoesOrOne
Registered Member
 
Join Date: Jun 2019
Posts: 37
Hi,
My dkh is way too high ( 13.4 in my opinion). First I thought about the salt mixture I am using (IO) which is supposed to make 11 dkh. What is making it more in my tank and how can I fix it.

Thank you


TwoShoesOrOne is offline   Reply With Quote
Old 06/22/2019, 09:29 PM   #19
TwoShoesOrOne
Registered Member
 
Join Date: Jun 2019
Posts: 37
Sorry should have been new thread


TwoShoesOrOne is offline   Reply With Quote
Old 06/23/2019, 01:16 AM   #20
dava6711
Registered Member
 
dava6711's Avatar
 
Join Date: Mar 2010
Location: England, UK
Posts: 140
Quote:
Originally Posted by TwoShoesOrOne View Post
Hi,
My dkh is way too high ( 13.4 in my opinion). First I thought about the salt mixture I am using (IO) which is supposed to make 11 dkh. What is making it more in my tank and how can I fix it.

Thank you
Your fix is an easy one.

If your calcium and magnesium are both at the correct parameters, and your elevated alkalinity isnít causing any problems to your livestock, Iíd simply leave it to come down on its own over time.


dava6711 is offline   Reply With Quote
Old 06/23/2019, 03:20 PM   #21
TwoShoesOrOne
Registered Member
 
Join Date: Jun 2019
Posts: 37
How do I know

Quote:
Originally Posted by dava6711 View Post
Your fix is an easy one.

If your calcium and magnesium are both at the correct parameters, and your elevated alkalinity isnít causing any problems to your livestock, Iíd simply leave it to come down on its own over time.
How do I know if it is causing problems to livestock? I don't want to risk waiting until something dies.


TwoShoesOrOne is offline   Reply With Quote
Old 06/23/2019, 04:00 PM   #22
bertoni
RC Mod
 
Join Date: Mar 2002
Location: Mountain View, CA, USA
Posts: 88,100
A long time ago, people ran tanks at 18 dKH for years because they thought it would increase growth. It didn't seem to cause harm. It seems possible for some tanks, particularly those that get carbon dosing, to have problems with higher dKH levels, but it's rare, and you'd have seen dead corals by now if that were an issue. We don't have a lot of hard data on the topic.


__________________
Jonathan Bertoni
bertoni is online now   Reply With Quote
Old 06/23/2019, 05:19 PM   #23
dava6711
Registered Member
 
dava6711's Avatar
 
Join Date: Mar 2010
Location: England, UK
Posts: 140
Quote:
Originally Posted by bertoni View Post
A long time ago, people ran tanks at 18 dKH for years because they thought it would increase growth. It didn't seem to cause harm. It seems possible for some tanks, particularly those that get carbon dosing, to have problems with higher dKH levels, but it's rare, and you'd have seen dead corals by now if that were an issue. We don't have a lot of hard data on the topic.
Youíre a great guy to have on this board, helping aquarists by passing on your wealth of great knowledge.


dava6711 is offline   Reply With Quote
Old 06/23/2019, 05:29 PM   #24
bertoni
RC Mod
 
Join Date: Mar 2002
Location: Mountain View, CA, USA
Posts: 88,100
You are very kind.


__________________
Jonathan Bertoni
bertoni is online now   Reply With Quote
Old 06/25/2019, 10:50 AM   #25
nereefpat
Registered Member
 
nereefpat's Avatar
 
Join Date: Apr 2016
Location: Central Nebraska
Posts: 3,152
Thanks for the update.

Evidence that getting Mg close to natural seawater parameters will help with Alk trouble.


__________________
Pat

Current Tank Info: 125 in-wall , 40b sump. 6 bulb T5. ASM G2 skimmer. LPS and leathers
nereefpat is offline   Reply With Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -6. The time now is 12:41 AM.


TapaTalk Enabled

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2019 Axivo Inc.
Use of this web site is subject to the terms and conditions described in the user agreement.
Reef CentralTM Reef Central, LLC. Copyright ©1999-2014
User Alert System provided by Advanced User Tagging v3.3.0 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.