Alkalinity going down

[davidwillis]

I am a bit confused as to why my alkalinity is going down instead of up.
I am using a trident, using the hybrid balling method. I just switched from just two part to the hybrid balling method, but I don't see how that would cause this.
Alk one week ago was 8.2, this morning it is 7.86 (according to Trident). I increased the soda ash last night, and it went from 7.9 to 7.84. Calcium in the last week has gone up from 413 to 430, with a lower dose.

specs:
300 gallong tank
alk 7.84
ca 430
mg 1464
PH: 7.9

I tested alk and ca with other test kits to verify (I have been testing all week, so I can verify ca is going up, and alk down)
Alk:
APi - 7
salifert 8.2
red sea 7.8
Ca:
salifert 420
red sea 450
last 24 hours dosage
soda ash: 43.85 ml. (I actually dosed double that, but am using a 50% concentration, so this is what I would have dosed using a normal concentration)
Ca: 36.3 ml
I don't see any precipitation in the tank, or where I am dosing (high flow area). I dose alk at night, and ca during the day.
Should I just keep increasing the alk dosage?
I just wanted to check before I keep increasing the dosage, in case it is something else.

The strange thing is that alk goes up during the day (when I am not dosing), and then down at night when I do dose.

I know I have heard of this happening if you dose too much alk (precipitation). But I don't think that is the case?

Is this just a case of the reading not being accurate? I just find it strange that the alkalinity goes down when I dose, and up when I don't

 

[EgotisticObeseChihuahua]

What is your magnesium at?? That could be a factor to the problem because magnesium keeps your alkalinity and calcium stable.

 

[davidwillis]

What is your magnesium at?? That could be a factor to the problem because magnesium keeps your alkalinity and calcium stable.

My trident says it is 1465, but I have not confirmed that with other test kits. Maybe I should.

 

[sfin52]

Do you have coraline growing like mad?

 

[davidwillis]

Do you have coraline growing like mad?

Yes, coraline is growing a lot. Anything new gets coated within a few weeks, and it is hard to keep the glass clean.

 

[EgotisticObeseChihuahua]

My trident says it is 1465, but I have not confirmed that with other test kits. Maybe I should.

1465 is a basic reading so I doubt it's your magnesium. I would try to give your tank time to adapt to your change because switching your dosages can be a pretty big change for a reef tank. additionally I would continue further monitoring of your parameters, and look for a drop in these changes.

 

[Randy Holmes-Farley]

I’m not sure I understand the issue. Are you controlling dosing (dose more) or is a machine auto dosing to a target alk (means a machine problem).

 

[Lavey29]

7.8 is fine but it could just be 5hat you tanknis consuming slightly more now for coral growth also but I would wait at least a week for further check.

 

[davidwillis]

I’m not sure I understand the issue. Are you controlling dosing (dose more) or is a machine auto dosing to a target alk (means a machine problem).

I have it setup to dose with a target of 8.2, but the alk dropped out of the range I gave it, so it went back to the standard dose. Because of this I increased the range (so it would adjust), and also increased the dose amount. I hope that makes sense. I did have it set to 30ml, but increased it to 40. Here are a some pictures.

It is actually dosing more soda ash now, so the machine seems to be working, but for some reason when I dose soda ash, the alk goes down, and the more I dose the more it goes down.

 

[davidwillis]

7.8 is fine but it could just be 5hat you tanknis consuming slightly more now for coral growth also but I would wait at least a week for further check.

Yes, I am not worried too much about the level, I am concerned that it is trending down, and the more I try to stop it the more it goes down.

 

[Randy Holmes-Farley]

If you do not see any problems with precipitation, such as gardening sand or accretion on pump impellers, then just up the dose. Alk demand will rise as pH rises, and as corals grow.

What exact two alk products did you switch between?

 

[davidwillis]

I was just dosing two part BRS soda ash, and calcium. I have just added the hyrbrid balling method (added Trace A- to the soda ash, Trace K+ to the calcium, and am dosing part c).

I will check pump impellers to see if I can see anything.

 

[Randy Holmes-Farley]

43.85 mL per day of my DIY recipe #1 (BRS uses that for their soda ash recipe) in 300 gallons is a very tiny dose. Only 0.2 dKH per day,

If I read that correctly, just up the dose.

 

[davidwillis]

43.85 mL per day of my DIY recipe #1 (BRS uses that for their soda ash recipe) in 300 gallons is a very tiny dose. Only 0.2 dKH per day,

If I read that correctly, just up the dose.

Yes, I don't have a ton of corals right now (they are mostly still small). Is it normal to for the alkalinity to go down after dosing soda ash? I guess that is my main concern that it seems like dosing more makes the alk go down rather than up.

I think I will dose another batch today during the day and see if that brings it up or down.

 

[Randy Holmes-Farley]

If you dose less than the demand, it is normal for alk to decline.

 

[Lavey29]

Yes, I am not worried too much about the level, I am concerned that it is trending down, and the more I try to stop it the more it goes down.

The movement is minor and probably consistent with normal coral growth and increased alk demand.

 

[davidwillis]

If you dose less than the demand, it is normal for alk to decline.

sorry, maybe I was not clear on what I was trying to say. I mean the alk will go up or stay the same all day when I am not dosing, but then go down at night when I do dose. Then when I increased the dosing amount, it went down even more. So it seems like dosing soda ash actually lowers the alk.

For example, I check alk at 7am, 5pm, and 1am, and dose alk between 5pm and 7am. From 7am to 5pm (no soda ash dosed), the alk stays the sam, or sometimes goes up. However between 5pm and 1am (while dosing), the alk goes down, and also from 1am to 7am (also dosing soda ash), the alk goes down.

Maybe it is just the inaccuracy of the trident, and just a coincidence that it always shows that it goes down after dosing. I just wanted to check and see if I was doing something wrong before increasing the dosage again.

 

[Lavey29]

Alk consumption is typically greater during the day when lights are on and photosynthetic process is occurring so alk dosing more effective during the day. Skeletal growth occurs more during overnight hours so more calcium demands then and more effective to dose calcium overnight. Magnesium is your buffer and PH levels rise and fall also between day and night as you know which can also affect your alk level. I light a fuge overnight to try and keep PH levels consistent over 24 hour period.

 

[davidwillis]

Alk consumption is typically greater during the day when lights are on and photosynthetic process is occurring so alk dosing more effective during the day. Skeletal growth occurs more during overnight hours so more calcium demands then and more effective to dose calcium overnight. Magnesium is your buffer and PH levels rise and fall also between day and night as you know which can also affect your alk level. I light a fuge overnight to try and keep PH levels consistent over 24 hour period.

I have been dosing soda ash at night to help keep the ph consistent (which it is doing very well).

So this also brings up the question, why does alkalinity go up during the day, when I am not dosing, and corals are using it the most? PH is fluctuating between 7.9 and 8. I also dose vinegar during the day, which actually makes my ph lower during the day, and it raises at night from the soda ash. So it sounds like I should dose soda ash during the day, which would probably reverse the ph swing to be lower at night and higher during the day.

 

[Lavey29]

I have been dosing soda ash at night to help keep the ph consistent (which it is doing very well).

So this also brings up the question, why does alkalinity go up during the day, when I am not dosing, and corals are using it the most? PH is fluctuating between 7.9 and 8. I also dose vinegar during the day, which actually makes my ph lower during the day, and it raises at night from the soda ash. So it sounds like I should dose soda ash during the day, which would probably reverse the ph swing to be lower at night and higher during the day.

There are various methods for maintaining tank stability and I don't use the soda ash or vinegar methods. I just like to keep things simple with easy 2 part esv bionic dosing. Alk during the day, calcium overnight. I use a fuge with chaeto to keep my PH consistent overnight and provide natural filtration. Magnesium only depletes at 1/10th the rate of alk and cal so I simply hand dose that weekly.

What salt mix are you using and what is the alk number there?