Alkalinity

[jaykatoo]

Hello everyone. I have a cora life biocube 29 with a few fish, inverts and live rock. It has been up and running for 4 months. Today I had my water tested by my local supplier and was told that the alkalinity was testing high at 13.4. All other parameter tested were ok and include:
Ammonia =0
Nitrates = 10
Nitrites= 0
pH= 8

I do weekly 5 gallon water changes with ro water That I get pre made by a different store due cost. I was told that the salt the other store is using is the cause for the high alkalinity. Any thought about this? Also, what can i do to stabilize the alkalinity? How dangerous is the alkalinity at this level. Thanks for you help!



Katoo

 

[jaykatoo]

Temp fluctuates between 77-81
Specific gravity = 1.024


Katoo

 

[Reefing Madness]

Not to worry, its not high enough to hurt anything, and your system should use some of it up.
Its more than likely the water your using.
What you can do is test the water your getting, and you can lower that ALK using Muriatic Acid, using small amounts will bring that number down for you, and therefore allow your tank to come back in line.

Adding 1/11,000 of the water volume as this acid will drop alkalinity by 1 meq/l (2.8 dKH).
You want a drop of 13-7 = 6 dKH, or 2.1 times that amount, so add 1/5,100th of the water volume.
13 gallons ~ 49 L
1/5100 of 49 L = 9.6 mL
Add 5 ml and stir well for a few minutes and see what alkalinity you get. Then dose again assuming it seems on the right track.
You'll need to aerate well after adding the acid to blow off the excess CO2 and bring up the pH.

 

[jaykatoo]

Reefing madness, thanks for the detailed explanation . I will check the new batch of water I get prior to adding to aquarium. Thanks again!!


Katoo