Sand's affect on ph?

Discussion in 'Water Chemistry' started by Grant, Sep 28, 2009.

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  1. Daniel072

    Daniel072 Giant Squid

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    Without going into a ton of details, your cc or aragonite sand is absolutely inert unless the ph of your water drops below 7.6. This is why barebottom tanks work and why those of us who run ca reactors have to use co2. The co2 drops the ph and causes the media to release carbonates. Although i think you should still switch your substrates (because cc is horrible for other reasons) it isn't the cause of your ph issues
     
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  3. Grant

    Grant Feather Duster

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    Here are the results from the test Luna suggested:

    Current tank ph: 7.7
     
  4. Grant

    Grant Feather Duster

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    Oops...

    Like i said, here are the results from Luna's test:

    Current tank ph: 7.7
    Inside glass w/ airstone: 7.7
    Outside glass w/airstone: 7.7

    I don't really understand what this tells me. What does this mean? and what should I do?
     
  5. lunatik_69

    lunatik_69 Giant Squid

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    I dont want to sound doubtful, but are your sure you did the test right?
    9 out of 10 times the outside test is always higher than the inside. Meaning that inside your house your Co2 levels are too high. I did this test a while back and my results where interesting to say the least. My inside test was 7.8-7.9. Went ouside and within 10 mins the ph jumped to 8.2, almost 8.3. Without knowing anything else about your system and your habits, I dare to say that either you did something wrong or your testing equipment may be expired. I'm not saying that your CC substrate isnt a factor, its just that in most cases the Co2 levels are just too high. When preforming WC, do you clean your substrate? If you havent cleaned it in the past 5 yrs, that may be your problem too.
    What I did to fix my ph problem was to crack a window 1"-1 1/2" open that was near the tank. So everytime the a/c starts up, its taking in fresh air across the tank(and house). My ph went from 7.9 to 8.1-8.2 in a matter of hrs. The ph even reaches 8.3 at times.
    I do have a question for ya, when you go on vacation and come back, have you ever noticed if your ph is higher than when you left? I just left for 2 days this past weekend and when I came back, my ph was 8.36 compared to 8.18 when I left.




    Luna
     
  6. Grant

    Grant Feather Duster

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    As far as the test kit..maybe, but I doubt it. I'm using a Salifert kit now (i've used many over the years with similar results). This kit i bought last month, but I guess it could still be old. The outside test may have been a little lower temp, so I guess I didn't account for that. I'm really considering a ph monitor soon.

    Against my suggestion, my wife likes to leave the living room back door open so our dog can come and go as he pleases. This drives me nuts (bugs, air/heat issues) but it does increases indoor oxygen (my tank is in living room). I haven't noticed a correlation between ph and the door being open (sometimes all day and night).

    So it's possible that indoor Co2 levels are not the issue and i don't have a ca reactor. I clean my substrate every other water change (so every 4 weeeks). I have never tested the ph specifically after vacation, so I can't really say how that would come out, although I see where you're going. If it's not indoor Co2, what else could cause this?
     
  7. Dingo

    Dingo Giant Squid

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    Have you ever observed your pH at higher temperatures like 80-82?

    PV=nRT --> n=PV/RT

    since pressure, volume, and R (.0821) are all constant, temperature will have an effect on gaseous CO2 molecules in your water. I don't know how profound this effect will be, but it's worth a try...
     
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  9. lunatik_69

    lunatik_69 Giant Squid

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    Your situtation boggles the mind(so to speak). If its not Co2 levels, your No3 isnt high enough to hinder the ph, you clean the substrate regularly.......wait I think I may know whats your problem. You need to "introduce" oxygen into your system. Try installing a few air stones in your system. One in the sump, DT or where ever you can. Try testing your water for O2 levels.


    Luna
     
  10. Grant

    Grant Feather Duster

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    Unfortunately, I had the same results at higher temps. I got my chiller this year at the beginning of summer. For years I battled temps of 81-84 with many fans. I finally got tired of the temp swings and massive evaporation. (I travel alot for work and my wife hates doing anything to the tank, like adding water to my ato reservoir.) But during those days, I could still never get my ph above 8. I now keep the 77-78 range for several reasons, mainly trying to increase O2 as much as possible. I still use 1 surface fan that comes on with the lights.
     
  11. Grant

    Grant Feather Duster

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    I can try an airstone in my system. I have a AquaC EV180 skimmer that produces tons of bubbles already though. How do I test for 02 levels?
     
  12. Grant

    Grant Feather Duster

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    I sure do appreciate you guys help. I certainly don't have all the answers. Lots of questions though.