Alk is dropping from ph increase

aaronn · Nov 29, 2021

I need some help. I have an IM40 tank that has been running for 18 months. I have struggled to maintain my ph levels in the tank from day 1. The tank has consistently run from 7.6 to 8.0. I have Had a HOB refugium running on the tank to try to help ph. It did not help. I have also gone through 4 protein skimmers in 18 months because the nano pumps do not last. after the last skimmer pump died I decided to make a change. I have purchased a Aquamaxx HOB 1.5 skimmer. I removed the refugium and installed the skimmer 2 nights ago. The significant improvement in the quality of the skimmer has had an immediate impact on the ph in the tank. I am now running to a high of 8.2 and a low of 8.0 and trending higher. The problem is my Alk has crashed at the same time. I have gone from testing at 8.7 through Apex Trident to 7.8 currently. The apex controls dosing of 2 part as well. I know my corals will consume more with higher ph. This seems to fast. Corals currently look fine. I need some input on how to proceed. I have verified the change in Alk thru my Hannah checker as well.

blaxsun · Nov 29, 2021

How much does your alkalinity swing during the day?

aaronn · Nov 29, 2021

My apex has been keeping it pretty stable. I generally don’t see it move more then .1 between tests with the trident controlled dosing. The drop was immediate to the skimmer being turn on and the ph spoke.

aaronn · Nov 29, 2021

You can see on the ph graph exactly when the skimmer was turned on. I am not sure if I should watch and see if it rebounds or start dosing extra Alk. I don’t like over reacting.