Why is my Alk increasing daily?

[KrisReef]

The round trip from food to nitrate and then consumed will have no alk impact. Nitrate needs to be rising or falling for alk to change.

Now I am completely confused.

 

[Randy Holmes-Farley Verified Community Expert]

Now I am completely confused.

Organic (food) to organic (tissue) has
no impact on alk.

Organic to ammonia has no alk impact.

Ammonia to nitrate depletes alk.

Nitrate to ammonia/organic adds alk, the same amount that was lost.

Unless nitrate is increasing or decreasing, these various processes cancel out with respect to alk.

 

[Dread Pirate Dave]

When alk demand is very low, the slow dissolution of calcium carbonate in the low pH regions down in sand and in rock pores can boost alk slowly and steadily.

I've read other posts about this, some were yours too, I believe. For my biocube I have to work at keeping nitrate and phosphate from bottoming out. (4 feedings a day for fish) It's lightly stocked with LPS corals so alk demand is low. It rises about 0.9 dkh between weekly water changes. I've considered throwing in a birds nest or two so I can fight it in the opposite direction. lol

 

[Reef Puncher]

always have spare kits on hand to test to verify your trident is accurate. I use a hydros IV to auto test my alk, and there has been times where its off, but i wouldnt havnt known without a separate test kit to verify. i actually use 2, hannah and salifert, to cross reference my hydros IV. its just piece of mind knowing your not dosing improperly or anything.
btw great job trying to get stable alk prior to adding corals. all to often people just throw corals in without having even remotely stable water parameters, then are shocked when their corals die.

 

[GP0801]

No hanna reagent in stock at my local shop so I ordered some. Should be in tomorrow morning so I'll check then. In the meantime though, I decided to calibrate the tridents last night with Neptune's calibration solution. Here are the readings now, makes a little more sense to me.

I really love the whole Apex system while it's all working but out of the Apex, Dos, and both Tridents, this device was the only thing that didn't give me an issue until now. Mind you they're all relatively minor issues in the grand scheme of things I guess but still frustrating considering the price of everything.

I guess it's partially my fault for not calibrating sooner and actually trusting their word that calibration isn't completely necessary and results won't change by much.

 

[GP0801]

always have spare kits on hand to test to verify your trident is accurate. I use a hydros IV to auto test my alk, and there has been times where its off, but i wouldnt havnt known without a separate test kit to verify. i actually use 2, hannah and salifert, to cross reference my hydros IV. its just piece of mind knowing your not dosing improperly or anything.
btw great job trying to get stable alk prior to adding corals. all to often people just throw corals in without having even remotely stable water parameters, then are shocked when their corals die.

Thanks but I have to be honest, I only learned this time because I've been there and done that. My first tank I killed a bunch of corals after I got dinos. That was about 3 years ago and I haven't been willing to try corals again until now.

 

[GP0801]

It seems that alk testers just seem to dislike me. Maybe my hanna tester needs to be calibrated too, I just got some new reagent and tested both my tank water and water change water. The hanna tests both came back at 7.3. The apex however has been consistently testing at 8.3 since it's calibration.

 

[Randy Holmes-Farley Verified Community Expert]

Test result inaccuracy is a serious problem in the reefing world. I especially worry about folks who don’t come to places like reef2reef and get warned about that likelihood, but just accept the values and create problems where none existed.

 

[EricR]

...lightly stocked with LPS corals so alk demand is low. It rises about 0.9 dkh between weekly water changes. I've considered throwing in a birds nest or two so I can fight it in the opposite direction. lol

I'm in the same boat -- all soft corals with a couple LPS so low alk demand.
Alkalinity started increasing noticeably (with no dosing) at about the 2 year mark.
For the last year, I've just been fighting it off with weekly LOW ALK water changes using Sodium Bisulfate.
*might not be the best solution but working for me

I've finally (recently) gotten to a point where alkalinity increase has slowed enough so normal water changes are keeping it reasonably consistent.

I also thought about adding some hard corals but don't have a lot of room so didn't think it would help much.
Good luck with your adventure!

 

[spicymikey]

Okay I'll see if I can find a testing kit somewhere.

First off, going from 8.3 to 8.8 is not in any way concerning and is sort of within normal fluctuating ranges . But what others said about trident accuracy is true. I would suggest you buy a hanna alkalinity, calcium, and even magnesium, testers. You cannot count on the trident calibration solution to be accurate, especially when it comes to alkalinity. The alkalinity especially can be way off from the number on the bottle. That's why I usually don't even use their calibration solution and just test my water with Hannah testers and then enter those numbers into the calibration process. If you do that then I find trident to be pretty accurate with the daily sampling

 

[LunaReefs]

Is nitrate declining? A drop of 50 ppm by consumption adds 2.3 dKH of alk. Your rise is much less.

Randy, this is fascinating to me. Where can I find the best education (in simple mind format, lol) to help me understand the science of the relationship between the elements that affect dKH. I have a basic understanding of Ca but would really love the master this topic. Thank you!

 

[Randy Holmes-Farley Verified Community Expert]

Randy, this is fascinating to me. Where can I find the best education (in simple mind format, lol) to help me understand the science of the relationship between the elements that affect dKH. I have a basic understanding of Ca but would really love the master this topic. Thank you!

There are very few that impact alk, and I detail them in the link below.

Besides water changes, the most important ones are declining, rising, or dosing of nitrate. Dosing ammonium chloride depeltes alk, but that's not especially common.

Sulfur denitrators are a huge hit to alkalinity, and if one adds calcium carbonate into them to dissolve in the low pH, it just shifts that issue to rising calcium.

I'm happy to discuss and clarify anything in the article:

When Do Calcium and Alkalinity Demand Not Exactly Balance? by Randy Holmes-Farley

 

[LunaReefs]

There are very few that impact alk, and I detail them in the link below.

Besides water changes, the most important ones are declining, rising, or dosing of nitrate. Dosing ammonium chloride depeltes alk, but that's not especially common.

Sulfur denitrators are a huge hit to alkalinity, and if one adds calcium carbonate into them to dissolve in the low pH, it just shifts that issue to rising calcium.

I'm happy to discuss and clarify anything in the article:

When Do Calcium and Alkalinity Demand Not Exactly Balance? by Randy Holmes-Farley

Great, thank you.

There are very few that impact alk, and I detail them in the link below.

Besides water changes, the most important ones are declining, rising, or dosing of nitrate. Dosing ammonium chloride depeltes alk, but that's not especially common.

Sulfur denitrators are a huge hit to alkalinity, and if one adds calcium carbonate into them to dissolve in the low pH, it just shifts that issue to rising calcium.

I'm happy to discuss and clarify anything in the article:

When Do Calcium and Alkalinity Demand Not Exactly Balance? by Randy Holmes-Farley

Thank you so much! I will dig into this tonight