Is my tank crashing? Alkalinity shooting

[Leelalie]

Hi everyone,
My tank was really stable since February 2021. I decided to add 2 lysmata amboinensis, and 3 soft corals. A green discosoma, a devils hand and a sarcopython.
All was well, beginning of March we decided to add sea weed. Caulerpa prolifera. One week after my first shrimp died, I check my water stats every 2 days as my tank is still young. 4 months. I noticed that the alkalinity is shooting. One week later second shrimp dead.
And the alkalinity is still shooting. Right now I'm at 1.43 Mep/l
I did change about 20 liters last week.

Can anybody tell me why and what to do, please?Tank stats

 

[monkeyCmonkeyDo]

1.46 dkh?

 

[Leelalie]

1.46 dkh?

Oop 1,43 meg/l

 

[monkeyCmonkeyDo]

That is so low! Lol
I am intrested in how it gets that low.
I think randy suggests you take bakijg powder and put it in the oven and make soda ash. He knows the formula to raise and will hoefully chime in.
D

 

[Deep]

Your Alk is dropping because it is being consumed by livestock ( and maybe due to nitrification). So what livestock do you have in the tank? Are you dosing for Alk or no? How often do you do water changes and how much each time ?

edit - From your build thread I see this is a 63 litre tank with some softies. So if your Alk is dropping it is probably due to nitrification.
You can just manage it with water changes.

 

[Leelalie]

Your Alk is dropping because it is being consumed by livestock ( and maybe due to nitrification). So what livestock do you have in the tank? Are you dosing for Alk or no? How often do you do water changes and how much each time ?

edit - From your build thread I see this is a 63 litre tank with some softies. So if your Alk is dropping it is probably due to nitrification.
You can just manage it with water changes.

Live stock :
No fish at this stage
3 corals A green discosoma, a devils hand and a sarcopython.
1 red leg hermits crabe
3 nassarius
Loads of small snails and astarina star fish.

waterchange every week. About 10 liters

I just bought some sea buffer to up the alk

 

[Jekyl]

I use baking soda to raise my alk. What salt are you using? That alkalinity is very low. With the shrimp did you do a VERY good job acclimating? They require a good acclimation for new tanks

 

[Leelalie]

I use baking soda to raise my alk. What salt are you using? That alkalinity is very low. With the shrimp did you do a VERY good job acclimating? They require a good acclimation for new tanks

Salt instant ocean
Yes I did the drip méthode for 45 min for the shrimps

 

[Jekyl]

Something isn't right then. I'm pretty sure IO mixes to above 11 also, maybe even 12dkh. Your coral shouldn't be consuming it that quickly

 

[Jekyl]

How are the rest of your parameters? A spike in nutrients can cause your alk to drop. How is your ph? If low then nutrients may be the culprit

 

[arking_mark]

Live stock :
No fish at this stage
3 corals A green discosoma, a devils hand and a sarcopython.
1 red leg hermits crabe
3 nassarius
Loads of small snails and astarina star fish.

waterchange every week. About 10 liters

I just bought some sea buffer to up the alk

A couple of thoughts here:
1. Given your weekly water changes, assuming you are using a quality salt, I don't think your 1.43meg/l is an accurate reading. What salt mix are you using? How are you measuring Alk?
2. If indeed your reef has depleted your Alk, it has also depleted your Ca. You will need to dose a balanced Alk and Ca. Just adding a buffer will unbalance your tank.

 

[Leelalie]

A couple of thoughts here:
1. Given your weekly water changes, assuming you are using a quality salt, I don't think your 1.43meg/l is an accurate reading. What salt mix are you using? How are you measuring Alk?
2. If indeed your reef has depleted your Alk, it has also depleted your Ca. You will need to dose a balanced Alk and Ca. Just adding a buffer will unbalance your tank.

I used redsea
Tétra strips
Jbl strips to test the water
All three indicated very low Alk.
The fact I introduced a caulerpa in my tank... I read some where they do depleat a tank quickly

 

[ss30]

I used redsea
Tétra strips
Jbl strips
All three indicated very low Alk.
The fact I introduced a caulerpa in my tank... I read some where they do depleat a tank quickly

Don't use test strips to test you need to by a test kit, Salifert are good.

 

[arking_mark]

I used redsea
Tétra strips
Jbl strips to test the water
All three indicated very low Alk.
The fact I introduced a caulerpa in my tank... I read some where they do depleat a tank quickly

I'm not sure where you are getting this information. Unless you are using calcifying macroalgae like Halimeda your algae will not be pulling down your Alk/Ca.

Even if you are using calcifying macroalgae, it wouldn't pull down your parameters as stated given your water changes.

I find it highly likely that your testing is off.

I recommend NOT buffering your tank until you can confirm your parameters and suggest you get your water tested at an LFS or purchase a more reliable test kit such as the Hanna Alkalinity Checker.

 

[Leelalie]

Thank you for the help, I will get the material necessary for the tests

 

[arking_mark]

Thank you for the help, I will get the material necessary for the tests

Some general advice I try to follow:

1. Nothing good happens fast in a reef tank. So triple-check before you make or believe any changes
2. Don't chase #s
3. Never dose anything you aren't measuring for
4. Make only one change at a time to your aquarium.
5. Most problems can be minimized with a larger water change and GAC

Other things to note...

• Alk/Ca is almost always consumed equally in a tank and should be dosed in a balanced way. We measure Alk as it's much less available so its percentage increase/decrease is more easily measured. A large increase/decrease in Alk will only result in a small increase/decrease in Ca which may actually be in the error range of the test.
• Most refers have target Alk/Ca ranges they want to keep for their tank and will independently dose to get those parameters initially there and then do balanced dosing. Occasionally, they will individually readjust those #s
• Individually adding Alk or Ca to a tank can unbalance your tank if you aren't accurately measuring for both of these parameters. Ca is harder to measure accurately.