Chasing alkalinity in a Fish Only

[Feet4Fish]

I can't seem to stabilize my alkalinity in my 185 fish only system. I can have it up 8.3 one day and two days later it is in the 6's. I dose kalk in my top off reservoir.

Is it simply a fish respiration/carbonic acid thing? Any thoughts?

 

[rock_lobster]

Food, bacteria, livestock all causes lowering of alkalinity. Use the BRS calculator and dose accordingly to how much is being consumed.

 

[Randy Holmes-Farley Verified Community Expert]

Carbonic acid doesn't impact alkalinity, but production of nitrate from ammonia does. So if nitrate is increasing, alkalinity will be depleting.

 

[piranhaman00]

Bump.

I am dosing alk in a fish only tank, is this crazy? Im assuming coraline is using it up. Does it matter what alk is? Im assuming pH swings will be more crazy, which I dont want. Thoughts on this?

 

[xxkenny90xx]

I would not concern myself with chasing Alk numbers in a fish only

 

[xxkenny90xx]

I wouldn't chase ph either

 

[HuduVudu]

Bump.

I am dosing alk in a fish only tank, is this crazy? Im assuming coraline is using it up. Does it matter what alk is? Im assuming pH swings will be more crazy, which I dont want. Thoughts on this?

It isn't crazy as long as you are not dosing Sodium Carbonate/BiCarbonate only. Then it is crazy.

Use a one part or Kalk. If you dose using two part then you need to do water changes.

 

[piranhaman00]

It isn't crazy as long as you are not dosing Sodium Carbonate/BiCarbonate only. Then it is crazy.

Use a one part or Kalk. If you dose using two part then you need to do water changes.

Im dosing sodium bicarb only. Why is that crazy? I dont care about calcium or mg, I am only dosing sodium bicarb as a buffer to pH.

I dont do water changes in this aquarium in question ever so I fear the alk will reach 0? Not sure if thats even possible, and then pH would swing more, is this true?

 

[HuduVudu]

Im dosing sodium bicarb only. Why is that crazy? I dont care about calcium or mg, I am only dosing sodium bicarb as a buffer to pH.

What if I put it this way ... you are dosing sodium. Does that help?

Every available salt for aquarists has a decent level of alkalinity in it, some are specifically "higher". Water changing will help keep your alk up or at the very least do nothing. Why would you think that your Alk would go to zero? PH will not swing more at lower alk it will just swing from a lower baseline.

Honestly if you are concerned about PH there are many other factors that go into it. Open your windows for a few hours and see how this affects your PH.

I always try to go for the simplest solution for problems in this hobby. They seem to work the best.

 

[Randy Holmes-Farley Verified Community Expert]

Bump.

I am dosing alk in a fish only tank, is this crazy? Im assuming coraline is using it up. Does it matter what alk is? Im assuming pH swings will be more crazy, which I dont want. Thoughts on this?

If you want the coralline to grow, yes the alkalinity does matter.

 

[Randy Holmes-Farley Verified Community Expert]

Im dosing sodium bicarb only. Why is that crazy? I dont care about calcium or mg, I am only dosing sodium bicarb as a buffer to pH.

I dont do water changes in this aquarium in question ever so I fear the alk will reach 0? Not sure if thats even possible, and then pH would swing more, is this true?

That's a fine choice as an alk supplement for a FO.

 

[Randy Holmes-Farley Verified Community Expert]

What if I put it this way ... you are dosing sodium. Does that help?

Every available salt for aquarists has a decent level of alkalinity in it, some are specifically "higher". Water changing will help keep your alk up or at the very least do nothing. Why would you think that your Alk would go to zero? PH will not swing more at lower alk it will just swing from a lower baseline.

The size of the pH swing is also dependent on the total alkalinity because lower alkalinity has lower pH buffering against swings.

i discuss pH buffering here:

Chemistry And The Aquarium: Boron In A Reef Tank

This article also discusses the sources and sinks for boron in reef tanks, and shows that while typical tanks may be slightly depleted in boron with respect to natural levels, most are not so significantly depleted that any correction is required. Nevertheless, how to test for and supplement...

reefs.com

 

[piranhaman00]

If you want the coralline to grow, yes the alkalinity does matter.

That's a fine choice as an alk supplement for a FO.

The size of the pH swing is also dependent on the total alkalinity because lower alkalinity has lower pH buffering against swings.

i discuss pH buffering here:

Chemistry And The Aquarium: Boron In A Reef Tank

This article also discusses the sources and sinks for boron in reef tanks, and shows that while typical tanks may be slightly depleted in boron with respect to natural levels, most are not so significantly depleted that any correction is required. Nevertheless, how to test for and supplement...

reefs.com

Thank you, this is what I was looking for.

 

[piranhaman00]

What if I put it this way ... you are dosing sodium. Does that help?

Every available salt for aquarists has a decent level of alkalinity in it, some are specifically "higher". Water changing will help keep your alk up or at the very least do nothing. Why would you think that your Alk would go to zero? PH will not swing more at lower alk it will just swing from a lower baseline.

Honestly if you are concerned about PH there are many other factors that go into it. Open your windows for a few hours and see how this affects your PH.

I always try to go for the simplest solution for problems in this hobby. They seem to work the best.

coralline algae. Dosing alk is very simple.

 

[HuduVudu]

coralline algae. Dosing alk is very simple.

Do you not understand that you are putting sodium in your tank and doing nothing to balance it or remove it? You are not just adding Alk, you are adding sodium too. That is not simple because how often have you measured you sodium levels? Do you think there are test kits for hobbyists to test those?

 

[Randy Holmes-Farley Verified Community Expert]

Do you not understand that you are putting sodium in your tank and doing nothing to balance it or remove it? You are not just adding Alk, you are adding sodium too. That is not simple because how often have you measured you sodium levels? Do you think there are test kits for hobbyists to test those?

Since sodium is the largest concentration cation in seawater by more than a factor of 20, it doesn't concern me if it rises some, especially in a fish only. Even in a reef tank, normal water changes go a long way to offset the rise in sodium and chloride. Craig Bingman shows the changes here:

Chemistry And The Aquarium: Boron In A Reef Tank

This article also discusses the sources and sinks for boron in reef tanks, and shows that while typical tanks may be slightly depleted in boron with respect to natural levels, most are not so significantly depleted that any correction is required. Nevertheless, how to test for and supplement...

reefs.com

 

[nereefpat]

Dosing any 2 part system will raise both sodium and chloride over time. That will be offset by water changes.
Kalk has that advantage, as it doesn't increase either one.

If you are testing for and dosing alk, it would make sense to me to test and dose Ca. It is really easy and cheap to do. An API Ca kit is about 6 bucks, and any bulk calcium chloride will work. And you can just dump in a big enough Ca solution to raise 50+ppm at any time without harm, unlike alk. FYI, if you are using 1 dKH of alk a day, that equates to about 7ppm Ca a day.

 

[HuduVudu]

Since sodium is the largest concentration cation in seawater by more than a factor of 20, it doesn't concern me if it rises some

Agreed
Note though that the poster is not doing any water changes and neither of us know how much he is dosing, nor how much he is changing or has changed the sodium. I agree that dosing sodium carbonate/bicarbonate is possible and maybe convenient (if you are already solid in your water changing), but often people are very cavalier about water changes and don't get that they are actually changing their sodium/chloride balances, and few are familiar with Balling.

I dont do water changes in this aquarium in question ever so I fear the alk will reach 0?

 

[piranhaman00]

Do you not understand that you are putting sodium in your tank and doing nothing to balance it or remove it? You are not just adding Alk, you are adding sodium too. That is not simple because how often have you measured you sodium levels? Do you think there are test kits for hobbyists to test those?

Please stop replying, you are not helpful, thank you.

Dosing any 2 part system will raise both sodium and chloride over time. That will be offset by water changes.
Kalk has that advantage, as it doesn't increase either one.

If you are testing for and dosing alk, it would make sense to me to test and dose Ca. It is really easy and cheap to do. An API Ca kit is about 6 bucks, and any bulk calcium chloride will work. And you can just dump in a big enough Ca solution to raise 50+ppm at any time without harm, unlike alk. FYI, if you are using 1 dKH of alk a day, that equates to about 7ppm Ca a day.

Yes, I dose alk and ca in a reef tank that I do water changes on, was just wanting to dose alk, thank for input I might do ca now as wel!

 

[HuduVudu]

Please stop replying, you are not helpful, thank you.

Perfect I will ignore you because you are just fishing to confirm your biases. Good luck.