Curious to know why... lighting & pH

[CanadianReefer]

So, over the last little while I have been reducing the dusk/dawn period on my aquarium. I am now on an 8 hr full spectrum T5 schedule, with only 30 minutes each of dusk/dawn (total of 9 hours).

This is a big change from what I was running previously and given the reduction, I had assumed a negative (lowering) impact on my pH. Interestingly, however, I've noted the opposite. My pH has risen. Not a lot, but about 0.15.

Just curious why this might be...???

 

[CanadianReefer]

Sorry folks. This was supposed to post in a general discussion, but I'm using the app and it automatically posted under emergency. Can't change It, so if an admin can do it for me, that would be awesome.

 

[Flippers4pups]

So, over the last little while I have been reducing the dusk/dawn period on my aquarium. I am now on an 8 hr full spectrum T5 schedule, with only 30 minutes each of dusk/dawn (total of 9 hours).

This is a big change from what I was running previously and given the reduction, I had assumed a negative (lowering) impact on my pH. Interestingly, however, I've noted the opposite. My pH has risen. Not a lot, but about 0.15.

Just curious why this might be...???

C02 drop? Is there more fresh air in the home?

#mods

 

[CanadianReefer]

Probably less. It's dead of winter here, so all the windows are shut and the heat is on constantly

 

[Flippers4pups]

Probably less. It's dead of winter here, so all the windows are shut and the heat is on constantly

Okay, same here. Been very cold.

.05 isn't much. Maybe within +/- with test kit or probe.

 

[Maritimer]

Moved to "Reef Aquarium Discussion" by request.

~Bruce

 

[CanadianReefer]

Moved to "Reef Aquarium Discussion" by request.

~Bruce

@Maritimer Thanks Bruce!
Any input on the issue? It went from 7.85 to 8.02 .... seems strange to me. I'm not complaining at all, but it just wasn't what I was expecting

 

[Maritimer]

Wouldn't be what I'd expect either. How are you measuring your pH? If you're using a liquid test kit, are you reading it at the same time of day you were previously?

I would have thought that pH would fall through the night, and with a longer night . . .

Bit of a head-scratcher.

~Bruce

 

[Daltrey]

I’ve learned to control the ph swing by running a light over my sump at night.

 

[CanadianReefer]

Wouldn't be what I'd expect either. How are you measuring your pH? If you're using a liquid test kit, are you reading it at the same time of day you were previously?

I would have thought that pH would fall through the night, and with a longer night . . .

Bit of a head-scratcher.

~Bruce

I am using a probe hooked up to a computer. Odd, right? It's consistently higher ...

 

[CanadianReefer]

I’ve learned to control the ph swing by running a light over my sump at night.

I've always done that it was constantly at in and about 7.85, and now it's consistently between 8 - 8.02. The only thing that changed was the lighting

 

[WWIII]

I've always done that it was constantly at in and about 7.85, and now it's consistently between 8 - 8.02. The only thing that changed was the lighting

How old is the probe? Have you calibrated it lately? That is a head scratcher for sure!

 

[Daltrey]

From reading up on it maybe lights do affect ph.

http://www.thereeftank.com/forums/f190/the-effect-of-lights-on-ph-levels-163505.html

 

[rock_lobster]

A consistent pH range of 8-8.02 would be incredibly impressive do you have a 24 hour chart like this?

 

[WWIII]

From reading up on it maybe lights do affect ph.

http://www.thereeftank.com/forums/f190/the-effect-of-lights-on-ph-levels-163505.html

They definetely have an effect on ph, but it's usually the opposite of what @CanadianReefer is experiencing. Ph goes up during the lighting hours and then falls when the tank goes dark, until the lights get fired up again the next day. That is the strange part?

 

[rock_lobster]

From reading up on it maybe lights do affect ph.

http://www.thereeftank.com/forums/f190/the-effect-of-lights-on-ph-levels-163505.html

They certainly do. Light allows photosynthesis which consumes CO2 and increases pH.

 

[WWIII]

The ph in my system gets as low as 7.8 in the morning before the lights come on and as high as 8.3 in the evening when the lights have been on all day. Just as another example

 

[CanadianReefer]

The ph in my system gets as low as 7.8 in the morning before the lights come on and as high as 8.3 in the evening when the lights have been on all day. Just as another example

I don't typically experience large swings. I have a huge refugium on an opposite lighting schedule and it keeps it fairly consistent. I grow different types of algae and mangrove

 

[CanadianReefer]

How old is the probe? Have you calibrated it lately? That is a head scratcher for sure!

The probe is about 5 months old. I haven't calibrated it recently, so I'll try that and see if it makes a different

 

[CanadianReefer]

I don't typically experience large swings. I have a huge refugium on an opposite lighting schedule and it keeps it fairly consistent. I grow different types of algae and mangrove

My system is also fairly large - 300g. That probably helps stability as well