alkalinity issue

[Nineteen]

My alk has been dropping recently and have been struggling to maintain a steady alk until the past couple of days. Finally manage to stabilize it at 8.3dkh.

However, the effluent from the CR shoots up to about 69dkh to get to this stability. I did this by cranking up my CO2 rate to 3 bubbles per sec but the Ph in my main tank suffers. It drops to 7.7.

Is there a cause for concern in the long term if the PH drops to 7.7? Is there a more efficient way of stabilizing my alk? Am I stressing my CR to cope with the alk requirement in my aquarium? If yes – should I upgrade to a bigger CR?

Currently, I am using Deltec PF500 with Rowalith C+ for the CR. My other parameters are;

Ca: 430
Mg: 1380

I am on zeovit. It is 600 litres sps aquarium.

Please help.

Thanks

[McCrary]

Have you posted this to zeovit.com?

[Nineteen]

yes but no replies yet

[McCrary]

I would let people who are using zeovit help you as the nutrient reduction and bacterial adjustments do things to the tank that most people don't have going on in theirs.

[kinktao]

what kind of test are you using to check your alk? Sometimes the test kits are bad.

[Nineteen]

I am using Salifert - just bought new ones about 2 weeks ago.