Question about Ph in RO water

[Mrod91]

Hey guys,

I have been buying premade salt water at the store but I realized I’m better off mixing my own water.
Ive been doing research, I ordered Tropic Marin Bio-Actif salt and a 4 stage ro/di filter.
I have a fluval sea Evo 13.5 with mixed sps, lps.

upon my research ive read the Ph in the water after going through the filter is really low, salt added still relatively low.

my question or concern is, how would I balance the ph to match my tank?

thank you in advance!

 

[Mrod91]

Anyone?

 

[homer1475]

Wish I could answer this with a more scientific approach, but you will never get your mixed up water to match your tank. PH is mostly effected by the CO2 in your home. The higher the CO2, the lower the PH, The lower the CO2, the higher your PH will be.

PH buffers for salt water are mostly and alkalinity supplement(higher DKH the higher the PH), but this comes at a cost of higher Alkalinity, and should not be used as it is only a temporary bump and will return to normal equilibrium after a short time.

This might get better traction in the Reef Chemistry section where @Randy Holmes-Farley could answer it in a more scientific way.

 

[Aqua Man]

My thinking is if you’re letting salt mix for 24hrs near your tank then ph should be close enough. Since like Homer said Co2 can have an impact.
Alk is also important, especially in a tank that’s small. Does not have to be exact, close is good.

 

[nereefpat]

the Ph in the water after going through the filter is really low

Nothing to worry about there. A person might think that RO water should have a pH of around 7, but in reality it won't. RO water is really unstable, and it absorbs everything. All will be fine after the salt mix is added and the saltwater is aerated for a few minutes.

It really doesn't do any good to check the pH of your RO water.

 

[EMeyer]

Nothing to worry about there. A person might think that RO water should have a pH of around 7, but in reality it won't. RO water is really unstable, and it absorbs everything. All will be fine after the salt mix is added and the saltwater is aerated for a few minutes.

It really doesn't do any good to check the pH of your RO water.

This. The pH of RODI water is irrelevant. When you mix it into a highly buffered solution like artificial seawater, the pH changes immediately.

Remember pH is really just the concentration of H+ ions expressed on a funny scale. The H+ concentration in pure RODI water is very very low relative to the buffering capacity of saltwater.

One less thing to measure Just focus on TDS.

 

[Mrod91]

Nothing to worry about there. A person might think that RO water should have a pH of around 7, but in reality it won't. RO water is really unstable, and it absorbs everything. All will be fine after the salt mix is added and the saltwater is aerated for a few minutes.

It really doesn't do any good to check the pH of your RO water.

thank you so much for this answer. Pretty simple then.