Reef Central Online Community
The Filter Guys

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 09/28/2017, 01:46 PM   #1
dubmaneh
Registered Member
 
Join Date: Sep 2012
Location: Toronto, ON
Posts: 148
Why did my Alk stop decreasing?

About a 10 days ago I had a 1.8dKH jump in Alk over 48hours. A BRS dosing pump malfunctioned (my fault for not changing the tubing), Alk jumped from 7.5dKH to 9.3dKH. Since then I have suspended WC's and stopped dosing in order to reduce levels back to around 7.5dKH. However, in the past 10 days my Alk has remained high at 8.9dKH.

What is going on?!?!

Previous to this I was dosing approx. 14ml daily of Randy's Recipe #1 and my parameters were stable.

The only change I made was to start dosing ZeoBak and KZ Sponge Power just before the Alk spike. But I don't see how that would contribute to Alk not falling in 10 days.

Other than losing my favourite Acro during the initial spike, all the inhabitants look happy. Aside from a few burnt tips, colouration of my remaining SPS never been deeper.

My thoughts:

1) Dosers were previously failing and I've been overdosing 2 part this whole time. Though I don't think this is likely as parameters had been stable.

2) The alk jump was severe enough to shock the corals and they are still recovering before growth and Alk consumption resumes.

3) N03 and P04 have dropped. Could the bacteria from the ZeoBak be consuming N03 with P04 and in the process producing Alk?

So confused.....

System info:

60 gallon (net volume) with sump.
10l Siporax
50ml Rowaphos in a fluidized reactor
Vertex 150 skimmer

Here is a history of my test results:

September 18, 2017 - Started dosing ZeoBak & KZ Sponge Power
Sg = 1.026
T = 79.5
KH =7.5dKH
N03 = 5ppm

September 20, 2017
Sg = 1.026
T = 79.1
KH =8.6dKH

September 21, 2017 - Took dosers offline
Sg = 1.0265
T = 79.5
KH =9.3dKH

September 22, 2017
Sg = 1.026
T = 79.5
KH =8.9dKH
Ca =460ppm
N03 = 5ppm

September 23, 2017
Sg = 1.026
T = 79.5
KH =8.9dKH

September 24, 2017
Sg = 1.026
T = 79.5
KH =8.9dKH
Ca =460ppm
N03 = 5ppm

September 27, 2017
Sg = 1.026
T = 79.5
KH =8.9dKH
Ca =460ppm
N03 = 2.5ppm
P04 = 0.009ppm


dubmaneh is offline   Reply With Quote
Old 09/28/2017, 03:35 PM   #2
Tripod1404
Registered Member
 
Join Date: Mar 2016
Posts: 1,545
I would say its option 2.


Tripod1404 is online now   Reply With Quote
Old 09/28/2017, 03:58 PM   #3
bertoni
RC Mod
 
Join Date: Mar 2002
Location: Mountain View, CA, USA
Posts: 86,886
I agree that the corals might be recovering still. Generally, there's not enough added alkalinity from denitrification or carbon dosing to make much of a difference. How much has the nitrate level dropped?


__________________
Jonathan Bertoni
bertoni is online now   Reply With Quote
Old 09/28/2017, 04:26 PM   #4
dubmaneh
Registered Member
 
Join Date: Sep 2012
Location: Toronto, ON
Posts: 148
Quote:
Originally Posted by bertoni View Post
I agree that the corals might be recovering still. Generally, there's not enough added alkalinity from denitrification or carbon dosing to make much of a difference. How much has the nitrate level dropped?


Nitrate has dropped about 2.5ppm.


Sent from my iPhone using Tapatalk Pro


dubmaneh is offline   Reply With Quote
Old 09/28/2017, 05:02 PM   #5
mcgyvr
Registered Member
 
mcgyvr's Avatar
 
Join Date: Sep 2003
Location: North Carolina
Posts: 15,586
#2 gets my vote also..


__________________
Being blunt and having fun
mcgyvr is offline   Reply With Quote
Old 09/28/2017, 06:46 PM   #6
bertoni
RC Mod
 
Join Date: Mar 2002
Location: Mountain View, CA, USA
Posts: 86,886
That nitrate drop won't make a significant change in alkalinity:

http://reefkeeping.com/issues/2004-12/rhf/index.htm

About 0.03 meq/L, I think.


__________________
Jonathan Bertoni
bertoni is online now   Reply With Quote
Old 10/08/2017, 07:09 PM   #7
dubmaneh
Registered Member
 
Join Date: Sep 2012
Location: Toronto, ON
Posts: 148
Thanks for the replies. Alk consumption has finally resumed although the burnt tips are quite bad.


Sent from my iPhone using Tapatalk Pro


dubmaneh 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 07:08 PM.


TapaTalk Enabled

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2018 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 © 2018 DragonByte Technologies Ltd.