Q about buffering stored RO water for PWC

[joeyfromlawrenceville]

Hi,
Just wondering if you all add the marine buffer to your 5 gal jugs ( reccomended amount for 5 gal) when you add the salt and store until needed, OR do PWC and then measure correct dosage to raise PH using total tank volume and add to tank directly.
It would make since to store it already buffered, just wondering why the pre made SW at the store isn't buffered, unless it is not a good idea to store it at that PH level?
PS:My tanks are usually at 8.2 , I'm using seachem marine buffer 8.3, 8.2 is lower than most of you guys's, but is constant. that is ok isn't it?
Thanks,

[Kurt_Nelson]

I don't do either. I just mix my salt with my water, and store as long as required. No buffering required on my part, although I do dose a 2-part Ca/Alk solution daily. But even before I started doing that, I never had an issue keeping my pH at 8.2-ish with just weekly water changes.

[joeyfromlawrenceville]

Originally Posted by Kurt_Nelson

I never had an issue keeping my pH at 8.2-ish with just weekly water changes.

No Kidding?, something is different here, I do a 10%+PWC weekly with IO salt, and using the cheap liquid drops test it appears to be around 8.0 the morning after. I am about to change salt to Reef crystals once my IO is empty , maybe that will be better. I have not had a PH reading of 8.2 with out buffer yet. I might need to go ahead with the investment of a PH meter and see what it really is.
thanks,

[Kurt_Nelson]

Check your pH in the evening... right after your lights go out. My guess is that you're around 8.2 at that time. pH will be naturally lower in the morning, just before the lights come on - and highest at night right after the lights go off. Seeing a 0.2 swing between morning and evening is pretty typical.

For that reason, it's always best to take your pH readings at the same time of day - that way you're comparing apples to apples.

For me, I'm using Reef Crystals, 10% water change weekly, and a salinity of 1.025. After my lights go off, I've never gotten a pH reading of less than 8.1-ish or so. It's normally somewhere between 8.2 and 8.4.

[Edit 1: I'd avoid the pH meter, for now. The thing I see with electronic meters is that people end up chasing pH numbers out to the hundredths decimal place, trying to get "stability". Micromanaging pH is kind of fruitless because if there really is something wrong, buffers will only give you a temporary solution.]

[Edit 2: I'd get a alkalinity test kit and see where your alk and calcium numbers are at. I'm thinking you might be creeping your ca/alk parameters out of whack by constantly adding buffer. I know I added buffer during my cycle because I thought my pH was low, and I was fighting my ca/alk levels for at least a month trying to get them back balanced. Here's a good article in case you need it...http://www.advancedaquarist.com/issues/nov2002/chem.htm ]

[joeyfromlawrenceville]

thank you sir,I'll do some reading. I had no idea it fluctuated by time of day, sure was hard to chase a moving target like that.
thanks again

[melosu58]

I agree with kurt that weekly PWC `s will do the job. I dont use a buffer and mine stays around 8.2 in the evening also like Kurt was saying. SW is a buffer anyway and most salt mixes can handle PH problems.