ph stability

[z_dano]

I've noticed that lately my ph keeps dropping from 8.2-8.3 to 7.9-8.0... It takes a few days 3-4 but I don't want to keep adding buffer to keep it regulated.
Is it due to surface agitation? If so do I need more or less? I can do either but am not sure which.
Thanks

 

[jcolon]

Is your tank still cycling? Sounds like it's using up it's buffers and cycling tanks do tend to drop pH as establishing bacteria consume minerals that buffer the water.

 

[z_dano]

No its already cycled, the tank is about 4 months old. I really haven't noticed the ph dropping like it has until the last couple of weeks. I did change my salt but I got better salt (red sea coral pro salt vs instant ocean salt) so it shouldn't be that. I have been using ro from my lfr also.
All of my params are good except the ph drop.

 

[z_dano]

I just repositioned the sump discharge to agitate the surface less than I was previously. I may need to do the opposite tho, I dunno.

 

[ccCapt]

What makes you think the Red Sea salt is better than Instant Ocean?
The change in weather can have an effect on pH. If you have your windows opened in the summer the fresh air will help keep the pH up. As it gets colder and the windows are closed co2 can rise in the house and lower the pH.

 

[z_dano]

I didn't look at it the way, with the house all closed up (live in new england). Would it make that much of a difference? So surface agitation has nothing to do with it?
As far as the salt goes, comparing brands? I don't know.
The coral pro has more nutrients due to it being reef salt compared to the instant ocean regular salt. So that is how I quantified the red sea being better. I understand every brand has its fans (i don't have a favorite).
I plan on putting in corals in a while and already have some mushrooms, xenia, and brain corals... they came on the bottom of some lr

 

[ccCapt]

Yes, fresh air has a big impact on pH. With the house closed up it's not unusual for your pH to drop.

As far as the salt, what extra nutrients are you referring to? Don't get fooled by advertising. While I do like Red Sea salt, I like the regular version better than the Coral Pro. With that being said.....I use Instant Ocean. Its a perfectly fine salt for any aquarium, including a reef full of corals.

 

[huma-huma]

Wait a minute. Fresh oxygenated air will DROP the ph. Put some tank water in a ziplock, seal it, and leave it alone for a few hours. The ph will be high. Let it sit with fresh air for an hour and itll drop. Anytime you expose water to fresh air, the ammonia can spike, causing the ph to drop. <7 is acidic, >7 is alkaline

 

[z_dano]

Nutrients - me being lazy and not looking up the minerals listed.
Do you supplement you water instead of using reef salt? Wouldn't using reef salt (regardless of brand) require less of the afore mentioned? What would you recommend for stabilizing my ph?

 

[ccCapt]

I dose calcium and alkalinity in my tank everyday because my tank is full of SPS corals. I would have to dose regardless of the brand salt I used. I don't dose anything else.
Your pH is fine at 7.8 - 8.0. Anything you dose to try and raise your pH will also raise your alkalinity.

 

[ccCapt]

Wait a minute. Fresh oxygenated air will DROP the ph. Put some tank water in a ziplock, seal it, and leave it alone for a few hours. The ph will be high. Let it sit with fresh air for an hour and itll drop. Anytime you expose water to fresh air, the ammonia can spike, causing the ph to drop. <7 is acidic, >7 is alkaline

WOW
Please take some time and read this article....
Low pH: Causes and Cures by Randy Holmes-Farley - Reefkeeping.com
"High indoor carbon dioxide levels can also lead to low pH problems in many tanks. Respiration by people and pets, the use of un-vented appliances burning natural gas (e.g., ovens and stoves) and the use of CaCO[SIZE=-1]3[/SIZE]/CO[SIZE=-1]2[/SIZE] reactors can lead to high indoor carbon dioxide levels. The level of carbon dioxide can easily be more than twice that of exterior air, and this excess can substantially lower the pH. This problem is especially severe in newer, more airtight homes. It is unlikely to be a problem in homes like mine where the wind can be felt blowing around old window frames.
Many aquarists have found that opening a window near the tank can significantly raise the pH within a day or two. Unfortunately, those aquarists living in colder climates cannot comfortably open windows in the winter. Some have found it useful in these situations to run a pipe or tubing from the outside to the air input of a skimmer, where fresh, exterior air is rapidly mixed with the tank water."