PH & ALK of Top off water

[ryshark]

Do you dose anything to bring up the PH or alk of your RO/DI water used for top off?

 

[melosu58]

I dont dose for that. Mine stays pretty much on target with just weekly PWC`s. Where is your`s at that you think you need to dose for?

 

[ryshark]

My top off water alk is 3 and ph is around 7. I was just curious if people bring the ro/di number up closer to the tanks numbers or just leave them be.

 

[melosu58]

As far as the PH that seems right for FW. You`ll get the desired 8.2 - 8.4 when you mix in the salt mix for PWC`s. What is your alk and PH on freshly made SW and your tank water. Just wondering

 

[roka64]

I pre mix my PWC and use a ph to adjust the pH of that water....not sure about Alk.

 

[ryshark]

I was referring to the RO/DI top off water that goes in the tank to replace evaporated water. Do you typically bring the PH or ALK up on that? My tank water has a PH of 8.0 - 8.3
I was just thinking maybe it would be more stable if my top off water had a higher PH and ALK.

 

[Kurt_Nelson]

I don't do anything to my DI water for top offs. My pH and alk are very stable from day to day, though I do dose a 2-part for ca/alk every day.

 

[ccCapt]

If you buffer your top off water, it's like dosing alk into your tank. When water evaporates, I don't think the sodium carbonate evaporates with it. I would think buffering top off water can easily throw your alk/ca balance out of whack.

 

[ryshark]

Thanks, I'll keep doing what I have been doing then which is leave the top off water as is, and dose the tank for alk and calcium

 

[melosu58]

That`s a good idea. I dont do anything to my top off water either.

 

[land locked]

Roka, what do you dose with? Are you dosing to raise or lower?
I hate to high jack the thread here, but I have noticed that my Ph has been slowly creeping lower and lower. Last night it was 7.9! I have been researching and there is lots of info about why Ph goes up, but not why it drops. I have been blaming it on some macro algae I got last month. Can anyone suggest reading on how to raise ph and what causes it to go low? I have been adding more an more coral too. Could that be it?

 

[ccCapt]

Low pH: Causes & Cures by Randy Holmes-Farley

 

[roka64]

More surface ripple will help to raise the pH. I don't dose my tank with anything, just pre mix my water and use a ph to get the correct pH as my tank.

 

[land locked]

Roka, Oh, I misunderstood you. Thanks for clarifying, I do that too. I thought that the increased surface ripple decreased your Ph?
cccapt, Thanks for the article that is exactly what I was looking for. I will read it this evening.

 

[roka64]

The more surface ripple, the more O2 exchange, thus the higher pH.