Alk demand decreasing?

[Aurortpa]

So tested before my water change yesterday, and noticed my alkalinity was 11—almost the same as last test 7 days ago @ 11.5, which hasn’t ever happened, so I did not do my usual dosing.

 

Curious, what reasons would alk demand would suddenly decrease or halt? 

 

My nitrates are under 5, if not near undetectable at times, so I am very gradually stepping up my feeding more. I did just start broadcasting zooplankton twice a week. The little left of my hair algae from my mini cycle has diminished almost entirely.

 

I typically feed fish daily except water change day, LPS get food twice a week, and balano a small piece of krill daily. Wondering if my corals are still hungry so growth might have temporarily halted?  Or are these “rest” periods common maybe?

 

I usually use IO which usually tests around where I keep my target alkalinity @ 11.

 

 

 

 

[ReefGoat]

Maybe it was just a bad test. Did you retest after getting the surprise reading? 

[Aurortpa]

1 hour ago, ReefGoat said:

Maybe it was just a bad test. Did you retest after getting the surprise reading? 

Yup. I don’t see anything out of the ordinary in terms of livestock conditions either...  Maybe my test last week wasn’t correct BUT typically my tank demands .5 dkh a day so was not expecting to be anywhere around 11 anyways—I’m more or less around 9.5 by the time I usually dose.  

 

[metrokat]

What level are you trying to keep alk at? I keep mine between 7.5-8.5

[A Little Blue]

Always test at the same time. Alk swings during 24h period. 

[Aurortpa]

7 minutes ago, metrokat said:

What level are you trying to keep alk at? I keep mine between 7.5-8.5

I aim for around 11. I’m gradually increasing my feeding alongside, coral health—color and growth—has dramatically improved.

[metrokat]

1 minute ago, Aurortpa said:

I aim for around 11. I’m gradually increasing my feeding alongside, coral health—color and growth—has dramatically improved.

You will see consumption of alk go up and down all the time. It has to do with growth as you observed, could be any number of reasons why there is a spurt or not. 

[A Little Blue]

Keeping it at 11 is tricky. Careful with light intensity and keep your nutrients up if you want to keep it this high. 

[Aurortpa]

2 minutes ago, A Little Blue said:

Always test at the same time. Alk swings during 24h period. 

True! TBH, I don’t remember if I tested at precisely the same time last week, but I still should have been down some dkh or is possible to swing that much at different times?  

 

The only thing that’s changed is the bottoming out of nutrients I believe. I noticed my skimmer the last couple weeks barely makes a couple teaspoons of veeerrryyy lightly colored skim now every few days. I don’t want to start pouring food in there suddenly so I’m trying to just feed a bit heavier. I used to count how many pellets things ate...lol. 

[Aurortpa]

Well goes to show you, things don’t ever stay quite the same!  It had even crossed my mind to just test monthly but forget that now! 😅

[A Little Blue]

10 minutes ago, Aurortpa said:

True! TBH, I don’t remember if I tested at precisely the same time last week, but I still should have been down some dkh or is possible to swing that much at different times?  

 

The only thing that’s changed is the bottoming out of nutrients I believe. I noticed my skimmer the last couple weeks barely makes a couple teaspoons of veeerrryyy lightly colored skim now every few days. I don’t want to start pouring food in there suddenly so I’m trying to just feed a bit heavier. I used to count how many pellets things ate...lol. 

From 9.5 to 11 is barely 1.5 difference. A little more than I would expect but possible. No need to freak out. Decrease or increase dosage amount (depending on your tank needs), dose at the same time(s), give enough time between  dosing 2 part solutions, clean vials, syringes etc in RO water. 

 

9 minutes ago, Aurortpa said:

Well goes to show you, things don’t ever stay quite the same!  It had even crossed my mind to just test monthly but forget that now! 😅

Monthly? How about daily??? At least till your tank matures and stabilize. Concentrate on testing Alk (preferably daily) and Ca (at least once a week or every other week). 

[Clown79]

Over the years I've seen alk consumption change. You won't have the same consumption all the time.

 

Corals may use more during growth spurts and then it may die down until the next growth period.

 

 

Even day to day can change.

 

I've seen it where for 2 days my alk drops but then for another 2 days it barely moves.

[A Little Blue]

9 minutes ago, Clown79 said:

Over the years I've seen alk consumption change. You won't have the same consumption all the time.

 

Corals may use more during growth spurts and then it may die down until the next growth period.

 

 

Even day to day can change.

 

I've seen it where for 2 days my alk drops but then for another 2 days it barely moves.

True.