LOW PH & ALKALINITY - Not CO2 problem

[SC Fish]

Hello Reefers, Getting back into saltwater tanks.... I have a 2 month old nano starting up. No issues with ammonia and nitrites. I feed very little amounts and do water 1/3 of tank water change every couple of weeks.The clown fish are very happy but PH stays around 7.5 and Dkh 4.5.

I have done the C02 test by opening windows test twice by leaving windows open all day. Basically no change in PH.

Everything points to the low alkalinity being the problem.....

I'm considering using a regular dose of Soda Ash or All for Reef for bringing up alkalinity... and hopefully stabilize PH at higher level. I did read it is normal for newer tanks to have a lower PH until bio filter matures more.... but not sure about this info. Any insights or knowledge would be helpful!

 

[Rmckoy]

What salt are you using ?
What test kit are you using to test alkalinity ?

and what salinity are you mixing your salt mix to ?
Measured with ?

 

[SC Fish]

What salt are you using ?
What test kit are you using to test alkalinity ?

and what salinity are you mixing your salt mix to ?
Measured with ?

Thanks,

I'm using Tropic Marin Synbiotic.

API test strips for alkalinity. Probably not the most accurate but seems roughly correct based on PH behavior. I have test ed PH with two different tests and both read the same

Salt count 34 ppt measured with a refractometer.

 

[Auquanut]

Your test results would indicate that the low Alk as the culprit. With your WC schedule, it seems unlikely that your Alk would remain so low. How well do you trust your refractometer? Have you calibrated it? They can drift way off of accuracy.

 

[Rmckoy]

Your test results would indicate that the low Alk as the culprit. With your WC schedule, it seems unlikely that your Alk would remain so low. How well do you trust your refractometer? Have you calibrated it? They can drift way off of accuracy.

If salinity is in fact 34ppt alk would be higher .
Either salinity refractometer is off or the api test strips are way off

tm isn’t generally this low

 

[SC Fish]

Your test results would indicate that the low Alk as the culprit. With your WC schedule, it seems unlikely that your Alk would remain so low. How well do you trust your refractometer? Have you calibrated it? They can drift way off of accuracy.

Your test results would indicate that the low Alk as the culprit. With your WC schedule, it seems unlikely that your Alk would remain so low. How well do you trust your refractometer? Have you calibrated it? They can drift way off of accuracy.

Thanks for your reply. I will check out your link. I did buy refractometer calibration solution. First, I zeroed out refractometer with RODI water. Then added 35 ppt calibration solution and adjusted to 35 ppm. Adjustment needed was very very slight between RODI and 35 ppt solution. There are only two 1.5 inch clown fish. Tank is pretty sparse other than Fuji pink live sand, and about 15 pounds of CaribSea rock. P.H reads about 8.0 when saltwater is mixed and ready to add to tank.

 

[SC Fish]

Sorry, just saw your follow up! I will buy new Alk test and refractometer to try and trouble shoot.

 

[Auquanut]

P.H reads about 8.0 when saltwater is mixed and ready to add to tank.

What does the Alk test at in your freshly mixed SW?

 

[SC Fish]

What does the Alk test at in your freshly mixed SW?

Tests with API strip color falls in the range of Tropic Marin projected 8-9 dKH.

 

[Auquanut]

Tests with API strip color falls in the range of Tropic Marin projected 8-9 dKH.

Okay. I gotta admit that I'm stumped. I can understand a new tank draining Alk out of the system to a certain point, but those numbers just don't make sense to me. What is your Calcium level?

Is there a chance that this young reef is heavily stocked with corals? Can we get a picture of the tank? I personally would consider investing in a more accurate Alk test kit (I use Red Sea) and conservatively dosing soda ash to bring your Alk up. If your Alk is a little high, it's better than being way too low in my opinion.

I'd like to hear what others have to say.

 

[Uncle99]

A fresh batch might test out high.
2 month, low or virtually no load, from 8dkh going in bi-monthly and reducing to 4.5dkh….something don’t seem right to me and “testing” error first came to mind like Auquanut posted.

I’d test for MG, might be low, and this can cause weird or false readings in ALK.

 

[SC Fish]

Thank you everyone for contributing thoughts in regard to other things to consider. There are no corals in the tank. I will definitely invest in different ALK test, refractometer, and do an update on the thread. But with the low PH, I was not surprised to see low Alk results. I do not have a calcium test yet... and probably should look at magnesium test kit as well. I'm baffled at the results with significant, regular water changes and only a couple of fish in the tank... seems strange.

I want stability before adding any more stock to tank. This tank is more of a display format which I know is not the most desirable format for reef aquariums. But it was a $2000 acrylic set up, owner had receipts, 1 year of use, (2) AI Prime LEDs, ATO, and lots of extras for $250.... I could not pass.

I'm not looking for difficult corals. Maybe a few soft corals for movement, a couple LPS and maybe one easier specimen of SPS. I do not want to jam it full and try and create an instant reef tank.... fine with taking some time. Photo attached. Thanks again everyone!

 

[Auquanut]

Sounds like you have a solid plan. In time, as you get comfortable with your testing and parameters, I'm sure your tank will achieve the equilibrium you need to create that awesome display. Looking forward to sharing in your successes.

Oh. By the way, I really like your aquascape!

 

[Rmckoy]

A fresh batch might test out high.
2 month, low or virtually no load, from 8dkh going in bi-monthly and reducing to 4.5dkh….something don’t seem right to me and “testing” error first came to mind like Auquanut posted.

I’d test for MG, might be low, and this can cause weird or false readings in ALK.

Extremely low mg would cause alk and cal to precipitate but to 4.5dkh ….

API.

 

[elysics]

Maybe get a sample of tank water (and maybe a sample of salt) to a reef store and have them test it. Could be a broken test, eare case of faulty salt or some weird fringe issue. There's no way that any kind of acid is getting into the tank somehow, is there?

And congratulations on the killer deal btw