New tank

[Dave0]

I have a brand new tank which was cycled using bottled ammonia, Colony and live sand for a few weeks. A week ago I added 2 clowns and 3 small frags.

During cycling, my alk started dropping and has continued- it's now down to six. I've just done a batch of newly mixed saltwater (Fritz RPM) at 10dKH.

What could be causing this drop -it can't be the coral as they are tiny wee things and the alk was dropping before I even put them in?

What should I do about it? As I see it my options:
1) Start dosing (seems a bit early in my reefing career to start having to do that!)
2) Be patient and do regular 10% weekly water changes and hope the alk goes up
3) Do a 50% water change to try and get the alk up more quickly
4) Find out what's causing the alk drop and kill it with fire

20G tank:
Salinity 35
0 ammonia, nitrite, phosphate
15 nitrate (I think this is high because I was using bottled ammonia for cycling)
No visible algae

EDIT: Looks like I've somehow managed to post this twice, no idea how. Also, no idea how to edit the title. It was supposed to read 'New tank, alk at 6 and dropping'. That's a newbie to the forums for you!
Thanks!

Dave

 

[MnFish1]

I have a brand new tank which was cycled using bottled ammonia, Colony and live sand for a few weeks. A week ago I added 2 clowns and 3 small frags.

During cycling, my alk started dropping and has continued- it's now down to six. I've just done a batch of newly mixed saltwater (Fritz RPM) at 10dKH.

What could be causing this drop -it can't be the coral as they are tiny wee things and the alk was dropping before I even put them in?

What should I do about it? As I see it my options:
1) Start dosing (seems a bit early in my reefing career to start having to do that!)
2) Be patient and do regular 10% weekly water changes and hope the alk goes up
3) Do a 50% water change to try and get the alk up more quickly
4) Find out what's causing the alk drop and kill it with fire

20G tank:
Salinity 35
0 ammonia, nitrite, phosphate
15 nitrate (I think this is high because I was using bottled ammonia for cycling)
No visible algae

EDIT: Looks like I've somehow managed to post this twice, no idea how. Also, no idea how to edit the title. It was supposed to read 'New tank, alk at 6 and dropping'. That's a newbie to the forums for you!
Thanks!

Dave

The first thing you should do is to double check the test. What is your pH?
There are at least a couple articles/posts here that describe how when ammonia is 'transformed' into nitrate, that alkalinity will drop (some). Then as the nitrate is 'used up' by other processes/bacteria, alkalinity will rise...

But I am curious - where did your alkalinity 'start'. I do not believe that the nitrate issue discussed above would cause a large alkalinity drop.

 

[Dave0]

The first thing you should do is to double check the test. What is your pH?
There are at least a couple articles/posts here that describe how when ammonia is 'transformed' into nitrate, that alkalinity will drop (some). Then as the nitrate is 'used up' by other processes/bacteria, alkalinity will rise...

But I am curious - where did your alkalinity 'start'. I do not believe that the nitrate issue discussed above would cause a large alkalinity drop.

The first thing you should do is to double check the test. What is your pH?
There are at least a couple articles/posts here that describe how when ammonia is 'transformed' into nitrate, that alkalinity will drop (some). Then as the nitrate is 'used up' by other processes/bacteria, alkalinity will rise...

But I am curious - where did your alkalinity 'start'. I do not believe that the nitrate issue discussed above would cause a large alkalinity drop.

I’ve triple checked the test as I just don’t understand how it can be so low! I annoyingly didn’t check the alk when I first did my big water change after the cycle finished, but just before it finished it was at 7. The ph has remained stable at 8.1

really don’t understand what is going on!

 

[MnFish1]

I’ve triple checked the test as I just don’t understand how it can be so low! I annoyingly didn’t check the alk when I first did my big water change after the cycle finished, but just before it finished it was at 7. The ph has remained stable at 8.1

really don’t understand what is going on!

I mean - double check - with a different 'test' - i.e. at your LFS - or buy a totally different kit. It would be hard for me to imagine an alkalinity of 6 and a pH of 8.1.

 

[Dave0]

I mean - double check - with a different 'test' - i.e. at your LFS - or buy a totally different kit. It would be hard for me to imagine an alkalinity of 6 and a pH of 8.1.

Ah, gotcha. Will do

 

[Dave0]

You were right - my pH test was off. Though alk was correct.

I did a 20% water change, which raised the alk temporarily but then started dropping again. It seems to have stabilised at 5.9 the last 2 days, so I'm going to dose with 'baked' baking soda for a4 or 5 days.

 

[MnFish1]

You were right - my pH test was off. Though alk was correct.

I did a 20% water change, which raised the alk temporarily but then started dropping again. It seems to have stabilised at 5.9 the last 2 days, so I'm going to dose with 'baked' baking soda for a4 or 5 days.

Curious - what was you pH - before (when incorrect) - and after?

 

[Dave0]

Curious - what was you pH - before (when incorrect) - and after?

pH registered 8.1/8.2 ish always (using API). When I got LPS to test, it came in at 7.4