pH help needed ASAP

[Eric B 125]

i use kati ani deionized water, which inherently can have a low pH, depending on the source water. never had a problem before, but my monti cap started dying off. did some tests... ammonia, trite, and trate were undetectable. pH was 7.6-7.8, calcium 440, kh 161.

i have on hand a bottle of aquavitro eight.four. can i just dose this into my return pump chamber? i know that pH is expressed logarhythmically (sp?) so i dont want to raise the pH too quick, eh? i'd raise it over 24 hrs. is dosing this way okay?

[dots]

Welcome to RC, even if it was already mentioned....

Ph has a natural swing daily. It can also vary with increased or decreased oxygenation with a skimmer or fish repiration.

Using a car analogy: The Ph can be viewed as a coil spring on the suspension. Without a shock absorber, the spring moves freely and easily. Alkalinity can be viewed as the Shock Absorbers. You can have fast acting or slow acting shock absorbers. High and Low Alkalinity has this same effect, low alk will allow the Ph to move freely, whereas the higher alk will lock it into place.

Depending on the test precision, it looks like your on the low side of the scale but wouldn't worry too much.

A water change and getting your Alk level and checking the Mg will go a long way to stabilize the system.

Your cap could be dying off from a number of other reasons, which will need to be looked into further. Low alk, is a place to start.

Additives rarely help with the exception of emptying your wallet. So, forget the aquavitro.

When listing test results, be sure to list the values and kits used. SG and other parameters.

Pictures help in a case like this, so we can address the issue.....the cap....at hand.

[Eric B 125]

i tried posting a picture in the original post, to no avail....?
i tested my top-off resevoir, too, which i filled earlier today. it tested real low too. so if the pH in the water is low, then raising the Alk wouldnt help, right? i realize that alk helps keep the pH stable and decreases the day/night swing.

[Eric B 125]

also, does pH tend to be lower at night, or after the lights have been on? i cant remember if the photosynthesis of corals and faster breathing of fish raises or lowers pH.

i should add, maybe, that i have a fuge with chaeto that is on an opposite light cycle than the tank.

[pkirby]

If it was me I'd try raising the ph SLOWLY over a couple days to 8.2 or somewhere around that. 7.6-7.8 isn't ideal, and I'd correct that to remove it as a possible source of your montipora poor health. If you are using an ATO, I would buffer the makeup water so it has the same ph as your tank and doesn't pull down your ph.

[aquadventure]

I agree with pkirby raising it to a more normal level slowly

[C0rp]

Start using aquavitro Salinity salt. My pH used to float around 8.0 +/-, after using Salinity its 8.3/8.4

[bnumair]

i use the salt Salinity and my ph runs 7.9-8.1. but i am using cal reactor and sulphur denitrator both causing low ph about 6.75-6.9 range. knowing that the salt does pretty good keeping up. recently i been adding ph 8.3 by seachem in y ro/di water top off barrel just to keep it on the up side. so it slowly gets mixed in my tank as needed and brings up the ph.