Urgent help needed!!!

[Genvid]

Dear fellow reefers, please help. Here is the situation: I have a 220-gallon reef tank. My parameters were: KH 8.2, Ca 480, Mg 1400, NO3 50, PO4 0.09, salinity 35, and pH 7.8. After reading several articles on nitrate removal, I decided to start dosing vinegar according to the specific chart provided on our site (50 ml daily). Today is the sixth day, and I noticed that three *Acropora* fragments have changed color. I immediately ran tests: KH 9.5, Ca 500, Mg 1410, NO3 60, PO4 0.08, salinity 35, and pH 7.6. I haven't been dosing anything for the past two weeks; the parameters seemed to have stabilized—neither rising nor falling. I perform a 20-gallon water change weekly using Modern Reef salt. My tank contains seven torch corals, ten small *Acropora* fragments, a couple of mushroom corals, and 5–6 other corals. Why did the alkalinity spike like that in just one day?

 

[Kooma]

Following along. If you started with 50ml that was likely too much, I dose 25ml of 10% acetic acid vinegar right now, I had it higher but was noticing cloudiness. Same water volume.

 

[Genvid]

 

[Kooma]

One thing to note is that this is 5% acetic acid, so look at what you bought and ensure yours is the same. I have 10% so 25ml is correct.

 

[Genvid]

Following along. If you started with 50ml that was likely too much, I dose 25ml of 10% acetic acid vinegar right now, I had it higher but was noticing cloudiness. Same water volume.

I dosed according to this table, and there was no clouding during dosing.

 

[Genvid]

One thing to note is that this is 5% acetic acid, so look at what you bought and ensure yours is the same. I have 10% so 25ml is correct.

 

[Genvid]

One thing to note is that this is 5% acetic acid, so look at what you bought and ensure yours is the same. I have 10% so 25ml is correct.

 

[Randy Holmes-Farley Verified Community Expert]

FWIW, declining nitrate from consumption adds alkalinity. 2.3 dKH of alk per 50 ppm of nitrate decline.

 

[Genvid]

Nitrate levels rose; they went from 50 to 60.

 

[Randy Holmes-Farley Verified Community Expert]

Then I expect the answer is among test error, salinity change, or unknown additive. Vinegar addition in any amount cannot
Boost alk unless you add so much that it lowers pH and dissolves some calcium carbonate.

In any case, I don’t think the alk change is a problem.

 

[Genvid]

I use Hanna tests and cross-check with Salifert. But why didn't the nitrates drop—why did they go up instead?

 

[Randy Holmes-Farley Verified Community Expert]

Test error? Nitrite formation? Less consumption? More feeding? Don’t sweat the small stuff, as test errors and small random changes are super common.

 

[Genvid]

I’m completely baffled; following a forum recommendation, I stopped adding anything—doing only fresh water changes. Yet, over the past two weeks, my Alkalinity has gradually climbed from 9 to 11.6. The water I use for changes—mixed with Modern Reef salt—has an Alkalinity of 7.9 at a salinity of 35. I bought Tropic Marin salt and plan to try a water change with it tomorrow. My goal is to get the Alkalinity down to 8.0. As of this morning, my parameters are: Alk 11.6, Ca 460, Mg 1390, and pH 7.9. I’m at my wit's end with this tank; I previously ran a Red Sea 350 for three years without a single issue. The tank contains mostly live Australian rock—all of it about four years old and previously established in a reef system. The tank itself is ten months old.

 

[Randy Holmes-Farley Verified Community Expert]

What is the other rock aside from the live?

Any sand?

These are the usual culprits.
Freshwater changes? What?

Is evaporation top off ro/di?

Aside from finding the source, water changes with a salt solution made to low or no alk will bring it down.

Here's a recipe:

https://www.reef2reef.com/threads/sodium-bisulfate-to-reduce-alkalinity-in-new-salt-water-or-in-display-tanks.362825

 

[allof fish]

I’m completely baffled; following a forum recommendation, I stopped adding anything—doing only fresh water changes. Yet, over the past two weeks, my Alkalinity has gradually climbed from 9 to 11.6. The water I use for changes—mixed with Modern Reef salt—has an Alkalinity of 7.9 at a salinity of 35. I bought Tropic Marin salt and plan to try a water change with it tomorrow. My goal is to get the Alkalinity down to 8.0. As of this morning, my parameters are: Alk 11.6, Ca 460, Mg 1390, and pH 7.9. I’m at my wit's end with this tank; I previously ran a Red Sea 350 for three years without a single issue. The tank contains mostly live Australian rock—all of it about four years old and previously established in a reef system. The tank itself is ten months old.

Are you dosing alk in any way? I find it hard to belive it is just rising without throwing any form of alk in the tank. Test kits can become inaccurate at times even if it’s a Hanna