HELP! ALK keeps dropping!

[VJV]

I don't know if this is on the right path, but here's a thought:



I noticed that you mentioned using buffer products like Seachem Reef Buffer. As I understand it, those generally contain a combination of chemicals intended to partially-kinda-sorta cancel each other out in ways that keep constant parameters. (Google can explain the chemistry better than I can.)



Plenty of unintended reactions can occur. At the extreme, if one part of the buffer is reacting with something unidentified, Weird Things may happen. I would only reach for a buffer if I had severe pH problems.



Have you tried using the plain alk supplement from a good 2-part mix, or simple baking soda (preferably baked -- search for related threads)?



Again, I'm no expect, just thinking this through...

[welcome]

Buffers generally are high-pH alkalinity supplements. They work by consuming carbon dioxide from the water column, basically. Unfortunately, aeration will bring carbon dioxide back into the water column, so the effects generally are short-lived, so buffers generally don't help much.

Thanks for the info! I did mention Seachem Reef buffer but I only tried it once to see if I got better results than I was getting with my Red Sea Reef Foundation Alk supplement. Red Sea's Reef Foundation is a 3 part solution with individual Alk, Calcium and Magnesium supplements.

Would you guys say that for a 80g reef tank with 7 LPS, 2 soft corals and no fish, a daily 1,4dKH drop is normal?

Thanks!

 

[bertoni]

That's a reasonable drop. My soft coral tanks consumed more than that due to coralline algae growth.

 

[VJV]

Coraline??? Never saw it! Not even one tiny spec of it...

 

[VJV]

Another update:
03/10
Alk: 8,4dKH (0,22dKH drop in 5 days, or roughly 0,04 per day)
Calcium: 436ppm (4ppm increase over 7 days)
Magnesium: 1320ppm (120ppm decrease in 7 days)

Alk: it is curious to see that after dropping 2dKH in the previous 2 days, even without changing the Alk dosage it is now almost flat.
Calcium: I had a water change in between measurements so not meaningful
Magnesium: this is being tested with Red Sea Pro titration test but I atibute the wild fluctuations more to errors on my side (difficulty in identifying the end result consistently).

 

[bertoni]

Okay, the drop seems reasonable, although the water change might have skewed the results.

 

[VJV]

I did not perform a water change between Alk measurements. I did a water change on the 25th. On the 26th Alk was at 9,63. On the 28th it was at 8,62, which would be a 1,4dKH drop per day taking into account that I was dosing 1,0dKH daily. A kept the dosage constant, and when I measured again in the 3rd of October the daily drop was almost insignificant over that period, even thou I had not changed the dosing. I will measure again tomorrow to see how did it fare over the past 5 days.

 

[VJV]

8/10 update. Alk was at 7,4dKH, a 1.0dKH drop in 5 days, in spite of the fact that I am dosing now close to 2.0dKH daily. .. Clearly something not working out.

I have noticed however that when the Alk supplement hits the sump it immediately turns into white flakes. Some hours later most are gone but I am convinced that I need to dose straight into the main display and see what happens.

I will try to set it up next weekend and see how it goes. If I continue to get this my next step will be to buy some good old Sodium Bicarbonate and ditch Red Sea Reef Foundation program altogether.

 

[bertoni]

Dosing into the main display was my choice, too. The white flakes likely are just magnesium hydroxide, but more water volume might help. I might check the inside of the pump as well.

 

[VJV]

HELP! ALK keeps dropping!

17/10: just tested and my Alk is now at 9,02 dKH ???? I did not increase the dosage last week so not sure how or why all of sudden the Alk is rising...!? And in fact I have been dosing 1.0dKH per day, not 2.0dKH as in my previous post. The only change was that las week I have finally moved all my fish (5) to the tank again, after 3 months of treatment...

Another curious result is that my Calcium dropped significantly and is now at 372ppm. Calcium has been relatively stable so it is odd that once I get Alk rising Calcium is now dropping...

 

[VJV]

Ca was at 432ppm on 8/10. A 60ppm drop. Dosed the equivalent of 20ppm straight to the tank and started a daily 8ppm dosing.

 

[bertoni]

Hmm, moving the fish might have changed the dynamics. I wouldn't worry much just yet.