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Thread: scrubber results

  1. #11

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    Its the green one, believe just the low one.

    Just tested it back to back, entire packet contents went in. .39 in both tests.

  2. #12
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    I have indeed seen fast-dropping phosphate in tanks with high phosphate that have no export. The scrubber is like a hole poked into the bottom of a 55 gal drum. Getting phosphate out of the rocks is a different matter.

    Turnover does not matter; scrubber take very little nutrients out of the water per second. And only the laminar layer of a fraction of a millimeter touching the algae does anything; the extra flow outside of that just passes by.

    Sounds like yours is working well.

  3. #13

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    Sm-


    So my numbers dropping can be true. How/when will I know if the phosphate is leaching from the rock?

    For instance, at the rate I'm going, another 25 percent WC or two I should be in teens or single digits. Does that sound about right, or are there barriers that exist the closer you get to zero?

    Also my nitrate is in the 10 to 20 range. Is that enough in water to keep phosphate coming down, or should I be feeding heavier? (The balance or ratio when either po4 or nitrate is to low, it can't remove the other etc)

  4. #14
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    Don't feed more. Nitrate does not affect the phosphate. This may help:

    Phosphate flow out of rocks

    Many people, when they get their scrubber running for the first time, get worried when more (not less) algae starts to grow on their rocks. It seems really strange, especially when nitrate and phosphate have gone lower than before. What is happening is that phosphate is coming out of the rocks. Remember, phosphate is invisible, so you can only see the effects of it, and it always "flows" from higher concentrations to lower concentrations (just like heat does).

    Example: If your room is warm, and you put a cold object on the floor, heat from the air in the room will "flow" into the object until the object and the air are the same temperature. Example 2: If you put a hot object on the floor, heat will "flow" out of the object and go into the air in the room, again, until the air and the object are the same temperature. Now suppose you open your windows (in the winter). The warm air in your room will go out the windows, and it will get colder in the room. The object on the floor is now warmer than the air, so heat will flow out of the object and into the air, and then out the window.

    Think of phosphate as the heat, and your rocks as the object, and your windows as the scrubber. As the scrubber pulls phosphate out of the water, the phosphate level in the water drops. Now, since the phosphate level in the water is lower than the phosphate level in the rocks, phosphate flows from the rocks into the water, and then from the water into the scrubber. This continues until the phosphate levels in the rocks and water are level again. And remember, you can't see this invisible flow.

    This flow causes an interesting thing to happen. As the phosphate comes out of the rocks, it then becomes available to feed algae as soon as the phosphate reaches the surface of the rocks where there is light. So, since the surface of the rocks is rough and has light, it starts growing MORE algae there (not less) as the phosphate comes out of the rocks. This is a pretty amazing thing to see for the first time, because if you did not know what was happening you would probably think that the algae in the scrubber was leaking out and attaching to your rocks. Here are the signs of phosphate coming out of the rocks:

    1. The rocks are older, and have slowly developed algae problems in the past year.

    2. The scrubber is new, maybe only a few months old, and has recently started to grow well.

    3. Nitrate and phosphate measurements in the water are low, usually the lowest they have been in a long time.

    4. Green hair algae (not brown) on the rocks has increased in certain spots, usually on corners and protrusions at the top.

    5. The glass has not needed cleaning as much.


    Since skimmers, filter socks, etc don't remove any nitrate and phosphate, and waterchanges and macro's in a fuge don't remove much, most people have never seen the effects of large amounts of phosphate coming out of the rocks quickly. But sure enough, it does. How long does it continue? For 2 months to a year, depending on how much phosphate is in the rocks, how strong your scrubber is, and how many other phosphate-removing filters you have (GFO, carbon dosing, etc). But one day you will see patches of white rock that were covered in green hair the day before; this is a sure sign that the algae are losing their phosphate supply from the rocks and can no longer hold on. Now it's just a matter of days before the rocks are clear.

  5. #15

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    Zero algae on glass, rocks or anywhere else but ats and surrounding chamber area . (is that a bad thing to have algae growing on sump glass which the ats PVC is housed? From escaping light from reflector?)

    And I always thought if you dropped nitrate to low, the algae would stop consuming both nitrate (gone, zero) as well as the phosphate.

    Suppose I need.some clarity on the ratio/balancing aspect.

  6. #16
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    Excess light in the sump just means more to clean.

    Nitrate can be any number.

  7. #17

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    Well cant figure this one out. Came home, after not feeding/touching the tank since this morning, tested, same procedure (clean vial with ro water, remove fingerprints etc) and my phosphate read .49, up a tenth from 12 hours ago. What could have possibly happened?

    I can tell that a lot of the lps are not as opened up as they usually are. Was going down down down, now phospate has risen up.

  8. #18
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    I would just stop testing for a while.

  9. #19

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    The normal range Hanna Checker Phosphate has an error range of +/- 0.04, so it's possible that your 2 tests prior read low and this one read high. I've tested back to back and got consistent results like you mentioned. So I don't know how true that is. But anyways I wouldn't concentrate on the exact reading as much as a trend of readings over time. i.e. test once a week, not one a day. Kind of like not weighing yourself every day when you're trying to lose weight.

    Also go through that process I posted. One key, which I think you have right, is not vigorously shaking the vial. I use the tip back & forth technique. You must get all the reagent dissolved. Also instead of rinsing the vial with water and wiping off with a paper towel, just use a glasses cleaning cloth. Not a microfiber cloth, not paper towel.

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