Can led intensity effect ph?

Just wondering if my led light with a intensity control could be effecting my ph? I have my 120w reef breeder light set at 60%. I also have an Apex controller with ph probe that was recalibrated last night. But I've noticed my ph climbs real slow throughout the day while light intensity slowly comes up. But when it hits 60% the ph seems to climb more rapidly. I'm currently working on getting my ph up to8.3 but its at 7.7 now. It dropped to 7.5 last night. The few corals I have acans, zoas, toadstool seem to be doing good. I haven't been wanting to dose buffer while probe needed calibrated. Just been doing water changes to help battle my gha. I've read that gha will deplete the ph? And you can raise Alk to help rid of gha? Amonia, nitrites, nitrates & phosphates are 0
Mag. 1280
Cal. 400
Alk. 11.5
Ph. 7.7
Temp 79*
Tank is 56g, 15g sump, urchin skimmer, vortech mp10, plenty of surface agitation to help with gas exchange. Currently no fish ( died of ich ), 2 skunk cleaner shrimp, 2 emerald crabs & few blue hermit crabs. I got some chaeto, crabs coming to help with gha.

 

Light in general effects pH. That's why if you have a refugium they you to run the lights on the fug opposite you regular lights so it balances out the pH swing.

 

Algae growth fueled by a lighting fixture will affect your pH value. As mentioned above this is the reason for the reverse lighting fuge.

Lowest pH value will be in the am before the tank receives any light source, the highest value will be at the end of the lighting period. The algae is releasing more CO2 at night driving down the pH.

 

Up to a point, the more photons hitting chlorophyll, the more oxygen is evolved, and the more CO2 is sequestered.

 

I've already got my 6500k bulb installed underneath. Just waiting for chaeto to arrive. I didn't want to be dosing buffer until probe was calibrated & I could start gaining control of gha. You guys know of raising alk to 14 dkh to help weed out gha? I also got a shaving brush tree to help. I don't ever hear of this being used to fight gha. Sorry Coraline but this probably don't belong in led lighting now. Lol my post started out as lighting question.

 

While I have never seen anything scientific or much in the way of anecdotal information, my personal experience is that if I maintain a higher pH I have less algae growth, but that is purely my own observation. While maintaining a higher ALK I am also maintaining a higher pH, but I would not go all the way up to 14 for an ALK.

 

I really haven't needed to use buffer according to my API test. Which is what got me wondering about ph in first place. I'm just glad I haven't seen bad effects towards my coral yet but that might of been culprit for my purple tilefish dying from ich. So I'm fishless til June.

 

This makes sense as there would probably be less CO2 in the water at higher pHs.

Higher alk can actually increase algae growth, since carbon would be available to plants as carbonate. Some microalgae growth mediums actually contain sodium carbonate in addition to the CO2 being bubbled in. Things can get quite complicated.

 

Definitely

I top off with kalk, when I miss a couple days for whatever reason I see an increase in algae growth, but I only have scant amounts of algae as it is.

 

In a nutshell, at lights out, all of the photosynthetic organisms go into what is known as "normal respiration", which means they use O2 just as you and I use it, and give off CO2.

As mentioned, this CO2 causes the pH of the tank to drop, since CO2 is acidic in nature.

Once the lights are on, these same organisms begin photosynthesis, where they use CO2 and give off O2, which returns the pH of the water back to "normal daylight" levels.

This is why one should never take pH readings first thing in the AM or after the lights have been out for awhile.