What is best to buffer R/O water?

[Ricerocket]

Would like to know what most people use to buffer their R/O water prior to adding top off to tank.

[Phoneguy982]

I was told there is no need to buffer RO/DI water. You can add buffer to it to maintain the PH of the tank but the water doesn't need the buffer before adding.

[weimluv1]

Phoneyguy is right. Adding RO/DI to a saltwater is not like adding RO/DI to freshwater.


when you add RO/DI water to your tank, it will mix with the tank water and become whatever pH your tank was to begin with.

However, separately from this, you should be measuring your alk and pH to make sure you have enough buffering cap. in your water, that is what you should be concerned with.


if you measurey your alk and pH and it is found to be too low, you can THEN add buffer to your topoff water to bring the pH and alk back up.

[Ricerocket]

What about Trace Elements? Would it be beneficial to add something to the R/O water that would replace what is taken out by the skimmer? Or should trace elements just be added regulary to the main system and leaving the R/O alone?

[bertoni]

I'm not sure exactly which elements you mean by "trace elements", but I wouldn't add iodine, iron, etc that way. I do use kalk in my top-off now, though. I use a peristaltic pump and a float switch to do the topoff, though.