Rising alkalinity

[Natalie]

A year ago, I took over a well established 30 gal reef aquarium with 20 gal refugium from my son prior to leaving for college. I am new to the hobby and was referred to you by Kevin at Aquatic Dreams in WA. My alkalinity is 3.70, ph 7.6 (tested at Aquatic Dreams, sample was about an hour and a half old), nitrates 0, nitrates 0, Ca 460. I have been doing biweekly water changes just to keep the alkalinity down. I use RODI water and have only been adding garlic and iodine on a weekly basis for zenias, who do not like the high alkalinity. I also have a clam, multiple stoney corals, a mandrin, orange-spotted goby with pistol shrimp, rainford goby, and clown with bubble anemone. My cleaner shrimp died several weeks ago, but everything else, aside from the pom pom zenias, looks good. Any ideas why the alkalinity would slowly rise?

Natalie

 

[ret25yo]

I got my calcium and alk. back up with 3 consequtive water changes over 3 days.

 

[Boomer]

Nat

Nothing can make your Alk slowly rise unless you are adding a buffer or have some DIY rock not cured right and it is going into solution. There are other issue however that can "seem" to raise the Alk. If, for example, you are adding something like Purple-Up or if Calcium is leaving solution and very small particles are floating around and you may not be able to see them, the acids used in the test kit will dissolve the CaCO3 and raise the Alk of the test, giving a higher Alk reading than you actually have. It could also be a test kit going bad.

 

[Natalie]

All my rock was purchased from an aquarium and has been in the tank for more than 5 years and I have only added garlic and iodine on a weekly basis. (I have stopped adding anything for the last 2 weeks). Kevin, owner of Aquatic Dreams in Spokane, WA, and I have the same Salifert test kit and have had similar test results. What could make ca leave solution and if that is my problem, how do I fix it?
Also my pom, pom zenias are looking better with an alk of 3.66 today.

Thank-you, Natalie

 

[-=dieseldave=-]

Whats the ALK and ca levels of the salt your using? What salt are you using?

 

[Willy]

All my rock was purchased from an aquarium and has been in the tank for more than 5 years and I have only added garlic and iodine on a weekly basis. (I have stopped adding anything for the last 2 weeks). Kevin, owner of Aquatic Dreams in Spokane, WA, and I have the same Salifert test kit and have had similar test results. What could make ca leave solution and if that is my problem, how do I fix it?
Also my pom, pom zenias are looking better with an alk of 3.66 today.

Thank-you, Natalie

I believe salifert has had some issues with alk test kits...I switched to lemotte after getting high readings on my salifert kit

 

[Natalie]

I'm using Oceanpure

Natalie

 

[Boomer]

What could make ca leave solution and if that is my problem, how do I fix it?

Nothing, as I stated above but to add a very low pH in the sand bed coupled with a low Alk and Ca+ tank level and that just dose not happen. Or it may be a rare chance there is a test kit issue with both kits. Try another brand. Or maybe the Oceanpure salt has some fine powdered aragonite in it giving false readings like Purple-Up.