Ph And Hardness Inconsistencies?

  1. samantha.h Member Member

    Hi everyone! Still working on getting my 75 put together.

    Today, I tested the water that is in the tank, and noticed some inconsistencies. Our water (well water) comes out of the faucet at a ph of about 6.6, and 6 degrees of both KH and GH hardness. The water in the tank is testing the same for the hardness, but the ph is 8.0. Does anyone know what might cause this? From what I understand, usually soft water has a lower ph.

    Tank info: sand substrate, granite rocks and driftwood for hardscape. Filter is a Sunsun hw304b with Matrix, foam pads, carbon, and polyfil. No fish or plants at this time. Nothing done yet to cycle the tank.

    It honestly baffles me because of the driftwood...I would think the ph would be even lower than what comes straight from the faucet, but it's not!
  2. Aquaphobia Fishlore Legend Member

    Most likely you have a lot of dissolved carbon dioxide in your well water. Try filling a bucket and running an airstone in it for a couple of hours to speed up the offgassing of the CO2. I bet the pH will rise. CO2 dissolved in water forms a weak acid, hence acid rain. To protect your fish from wild pH swings you may have to run an airstone in buckets of tap water before adding it to your tank.
  3. samantha.h Member Member

    What if I want the ph to be 6.6-6.8 in the tank? I know I can add peat, but is there something else that can be done besides RO?
  4. Aquaphobia Fishlore Legend Member

    RO would likely be the easiest way to achieve that pH if your natural pH is 8.0!
  5. Anders247 Fishlore Legend Member

    Do you need the pH to be low? I wouldn't mess with it.
  6. samantha.h Member Member

    Hi Anders,

    For the fish that I want to eventually stock, it sounds like the ideal ph is about 6.8 or 7.0. Unless it doesn't matter.

    Link to what I'm hoping to stock: Stocking Suggestions For 75g
  7. samantha.h Member Member

    My main concern are the cichlids (angels, GBRs, and apistos).
  8. Aquaphobia Fishlore Legend Member

    It doesn't matter. Your choices are S. American cichlids and they're not so demanding. They do like tannins though which are acidic and will help to drop your pH slightly ;)
  9. Anders247 Fishlore Legend Member

    I wouldn't mess with the pH for those fish. They should be fine.
  10. samantha.h Member Member

    Thank you both! I would have replied sooner, but for some reason I can't make posts from my phone like I used to be able to.
  11. AllieSten Fishlore VIP Member

    I would set a glass of water out over night and then test the tap water pH. That will give you your true pH reading.

    You will definitely have to watch out with water changes if there is a huge gap between tap and tank. You may need to leave your replacement water out over night to achieve the right pH for water changes. Or add an airstone for 6-8 hours to help the gasses dissipate. With water changes you don't want a difference of more than 0.4 between the tank and the replacement water, or you could have potential fish deaths.
  12. samantha.h Member Member

    Thanks for your reply. It reminded me that I need to do an update!
    I did leave a glass of water out for a day. Tested it, and it is reading the same as the tank now!

    My new issue is my API liquid test kit...the regular pH test reads dark blue, which is 7.8 I believe? When I test with the high pH test, it appears to be reading at 7.4. I don't understand why it would be 7.8 on one, but 7.4 on the other?
  13. Aquaphobia Fishlore Legend Member

    There is very little overlap so one is going to be accurate. If one of the test tubes matches the card colour closely then choose that result. Those two results are pretty close though, I wouldn't worry about it.
  14. Anders247 Fishlore Legend Member

    It's probably around 7.6.