PH still seems low for some reason

[b4tn]

My tank is about 3 months old now. I have several fish and and a few corals and have noticed small spots of coralline growing. But for some reason my PH is always 7.9 at night and rarely goes above 8.1 during the day. I have tested using both a probe and an API test kit. I use reef crystals, have a 2" aragonite sand bed, and used BRS reef saver rock. The water should get plenty of oxygen with my skimmer running 24/7 and lots of flow with two RW series pumps. In addition to that I have a waterfall scrubber running in my sump and I am dosing BRS two part. My levels stay pretty stable, last test I got 1300, 430, and 9.2.

I feel like I'm covering everything and everything seems healthy. Should I not worry about it?

 

[reef life]

Your PH is not extremely low. My motto is if it Aint broke , don't Fix it. Ha.(I went down that road before chasing the ph and ended up killing some corals)

 

[surfnsalt]

7.8 to 8.4 is acceptable range and it looks like your darn close to the middle.

 

[mrmole83]

Dont touch it

 

[b4tn]

Ok then, I wont mess with it.

 

[Downbeach]

Those numbers are fine, I ran a mixed reef successfully for many year with readings of 7.8 to 8.1.

 

[Virtualbasil]

Baking soda can make it go up if you begin having problems. Also a alkalinity additive will also.

 

[Downbeach]

Baking soda is an alkalinity additive, and will raise your alk readings, but due to the CO2 content it will temporarily lower your pH a bit. At an alk of 9.2 dKH alkalinity isn't your problem. The CO2 in your household atmosphere is going to be elevated any time of year you have to close the house up, and that is what's affecting the pH in your system. You could add kalk to your ATO which will utilize some of the CO2 in your system, elevating the pH a bit, but you may have to adjust your two part dosing. You could also run an airline from your skimmer air intake to an outide air source if practiable(lower CO2 = higher pH). A well lit healthy fuge would also make a difference(also taking up CO2).

 

[Newb73]

Most likely your issues is some function of the reduced lighting, CO2 in the home and or dissolved contents in the water.

With proper circulation, a good running skimmer, a good lighting set up and schdule (as well as an off-set fuge light) my PH bottoms out around 8.1. I could easily run it higher but id risk swings into the high 8.3s during the day when the lights are on. I keep a CO2 scrubber handy for when we are running the gas logs but I find it is not necessary to deploy it unless it is really cold outside and or I have a lot of people in the home. A couple things that I think helps are dosing alk at night or setting up the ato/kalk to mostly run at night.

As others have said, down to 7.8 or 7.9 is not an urgent problem. People say don't chase PH and to some degree I agree with them but I also see chronically low ph issues as a symptom of some husbandry that could stand to be improved...unless you just have a really tight home or the tank is in an area with poor circulation in which case its just a CO2-scrubber solution.

In my limited experience this is also more of a problem in smaller tanks (120g or less) and or tanks that are stocked too heavily