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Poor Efficiency in CO2/pump design: What are the options for increasing CO2?

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  • Poor Efficiency in CO2/pump design: What are the options for increasing CO2?

    Hi,

    90gal CO2 tank now 4+ months old. About a month ago I was just starting to congratulate myself (or more accurately, thank Tom for his advice that I followed [in some cases against my own judgment]) because I had seen NO ALGAE.

    Then some GSA and hair algae started to crop up. I killed VERY large clumps of needle leaf java fern spraying with 100% excel.

    I adjusted flow patterns.
    I pointed CO2 output directly into plants.
    I did H20 changes frequently.
    I recycled CO2 by bringing "false gas valve" of AM1000 back to pump intake.
    I turned up bubble rate so it is so fast I can no longer count (maybe 8-10+ bps).
    I just reduced photoperiod.

    I'm hoping you friendly folk will offer me some input. I assume inadequate CO2 is responsible for my GSA, and thread algae.

    I'm interested in whether my current design is adequate. On the surface it seems it should be --more than adequate-- for a 90gal tank. But apparently it is not, or I am not tuned in to what to change, and this is my problem.

    The attached diagram illustrates my CO2 design. One possibility is to get rid of the AM1000 with tiny 1/2inch I/O and replace with larger reactor (3/4"? I/O). If I do that, same pump OK? I'm kinda lost in what to change.

    What options, for my set up, would seem to make sense for enhancing CO2?

    thanks for any feedback,
    growitnow

    90gal
    KNO3: 15ppm, 3x
    KH2PO4: 6ppm, 3x
    K2S04: 17ppm, 3x
    Trace (TPN): 25ml, 3x
    Iron (Seachem Iron): 15ml (.44ppm), 3x
    GH booster: 4tsp at WC
    Mg: 10mg (3ppm) at WC
    Lighting: 4x55w CF, 9hours total (8hrs @ 110w, plus 1hr @ 220w)

    Plants: Staurogyne, Blyxa (never done that well), H. angustifolia, needle leaf java fern
    Fish: Congo Tetra x 4, SAE x 4, plus 6 or so tetras

    Equipment:
    Eheim 1260 (635gph) which drives AM1000 reactor
    Eheim 2128 x 3


    (BTW: can I post the PDF or .doc image, inside this post or must I attached it)
    Last edited by growitnow; 10-10-2010, 08:06 PM.

  • #2
    GSA has two causes, low PO4 and/or CO2. Low PO4 is the easy one. Your PO4 level should be between 3 and 5 ppm all the time. CO2 is most likely the problem, which shows in your Blyxa, that doesn't do that well. Blyxa is a real weed, when it gets enough CO2.

    What I would do is close the false gas valve of the AM1000, you're outgassing more CO2 than the tank uses. Then cut the AM1000 barbs and modify to accept the standard Eheim 16/22 mm size hoses. This modification eliminates the bottleneck and enhances flow. The AM1000 is capable enough to handle a 90 gallon tank, but I bet the flow is no more than 150 GPH now.

    Turn on your CO2 early enough so desired CO2 levels are reached when the lights switch on.

    regards,
    dutchy
    Last edited by dutchy; 10-10-2010, 09:06 PM.
    regards,
    dutchy.

    My 2011, 2012 and 2013 AGA aquascaping contest entries:
    http://www.barrreport.com/album.php?u=21013

    Comment


    • #3
      Hi dutchy, thanks for feedback.

      1) false gas valve has been closed since set up. I just opened it about 4 days ago, as test to see if chopping up gas would be better. Tom and others have suggested doing this, also on DIY versions. I would be grateful if you might clarify why this is an undesirable thing, since I was under the impression it should enhance CO2 levels/efficiency (or perhaps what's wrong with with the way that *I* am doing this).

      2) cutting off I/O barbs of AM1000. I know you've done this successfully, I believe installing 3/4" fittings on your AM1000. I gather you drilled 3/4" holes in the lid and bottom of the AM1000. Then, did you use plastic weld to fit hard 3/4 PVC to the drilled cap/bottom of the AM1000? Also, from your tank pics (which are fantastic!) I cannot see how water actually exits the 3/4 pvc line? What do you connect your 3/4 pvc from AM1000 to that actually dumps back into tank?

      3) If I fit the AM1000 with 5/8" barbs, should I retain the same 635gph pump. Or get a bigger one.

      4) At the tank return side (as per my diagram), my 5/8" ehiem hose is connected to 1/2" loc-line. Will increasing the size of I/O holes in the AM1000 increase output if I retain the 1/2" loc-line output fixtures? Or should I fit the 5/8" eheim hose out of the AM1000 to new 3/4" loc-line fixtures and get rid of the 1/2" loc-line?

      Thanks,
      growitnow

      Comment


      • #4
        Not As Smart, Though Certainly Better Looking

        Hi growitnow,

        Not Dutchy and I am not smart enough to understand the “false gas” problem, I had also understood that it was a (good?) method to improve CO2's rate of dissolving. So I will leave that alone.

        I honestly cannot see any obvious problem based on your description.

        At four months, your tank is still a baby, most systems take at least six months and I think more like a year to mature and stabilize.

        The GSA really is of little concern beyond the nuisance factor.

        I recommend 10 milliliters of Fleet Enema or 2 grams of KH2PO4 into 250 milliliters of distilled water at each 50% (70% would be better) water change. Before replacing the water, wet a paper towel with the solution and wipe all of the glass from top to substrate and any hard surfaces that are exposed. Add any remaining solution to the water column.

        Remove as much hair and any other algae as possible.

        Do this at least once a week, if possible, three water changes, one every other day would help.

        Obviously check for CO2/circulation problems.

        This is a young tank and somewhere along the way you got a build up of organics that got beyond the ability of your filtration to handle.

        Make sure your filters are clean and unobstructed.

        Go easy on the Excel.

        Biollante
        The first sign we don't know what we are doing is an obsession with numbers. - Johann Wolfgang von Goethe

        Disclaimer: I am not trying to make you mad, it is just what I am, an evil plant monster, 'nuf said.
        • I believe the information I am giving is sound, I am not a veterinarian, professional chemist or particularly bright and certainly not a "Guru.".
        • I assume you are of legal age, competent and it is legal for you to acquire, possess and use any materials or perform any action in your in your jurisdiction.
        • When in doubt "don't."

        Comment


        • #5
          If I understand this correctly your 90g has been looking good for about 4 months? Good plant growth + no algae?

          If this was the case, it seems that your best starting point would be to figure out what *has* changed, rather than making deliberate changes to your set up and confussing yourself.

          Light -> Your light has been constant? Constant intensity + photo period? Sure, the lights will dim slighly as they age, but this will reduce nutrient/co2 demand.

          Ferts -> As the plants have grown in over the last 4 months, their nutrient demands would have gone up - but this should be easy enough to rule out if you have been E.I. dosing? You have been dosing E.I. haven't you?

          CO2 -> the only thing left, and the most likely culprit as the other gurus have mentioned earlier. As the plants fill in, that will demand more CO2. Tell tale signs, such as the algae you are seeing now, could simply indicate that you need to tweak your CO2, i.e. push it a little harder to match increasing demand.

          Has your water temperature changed? Where you live, has the weather become warmer, such that the water in your 90g is getting warmer? As the water warms up, you will have to push the CO2 harder too. Could this be the root cause?
          6' Planted Tank (72" x 18" x 20") - 4 x 30W T8 Tri-Phosphors - 2 x Eheim 2217 'Classic' canisters
          Flourite substrate - Ocean Runner OR-2500 + AM1000 - Tunze Turbelle Nanostream 6045
          6.8kg Catalina CO2 - Red Sea Pro regulator - Swagelok B-SS4-A metering valve - Vecton 600 UV

          Comment


          • #6
            Lighting: 4x55w CF, 9hours total (8hrs @ 110w, plus 1hr @ 220w)
            Just an extra thought - I don't think the 1 hr blast at 220w is necessary? I can't see any reason why you can't just run 2x55w for, say, 9 hours?
            6' Planted Tank (72" x 18" x 20") - 4 x 30W T8 Tri-Phosphors - 2 x Eheim 2217 'Classic' canisters
            Flourite substrate - Ocean Runner OR-2500 + AM1000 - Tunze Turbelle Nanostream 6045
            6.8kg Catalina CO2 - Red Sea Pro regulator - Swagelok B-SS4-A metering valve - Vecton 600 UV

            Comment


            • #7
              Originally posted by growitnow View Post
              Hi dutchy, thanks for feedback.

              1) false gas valve has been closed since set up. I just opened it about 4 days ago, as test to see if chopping up gas would be better. Tom and others have suggested doing this, also on DIY versions. I would be grateful if you might clarify why this is an undesirable thing, since I was under the impression it should enhance CO2 levels/efficiency (or perhaps what's wrong with with the way that *I* am doing this).
              I know I have a different opinion here than Tom, but the reason is I tried the same for some time. The only thing I noticed was that I was using about two times as much CO2 as before without noticing any worthwhile differences. So this is more about efficiency, not an issue of better/worse results. (Your topic title was "poor efficiency"
              Originally posted by growitnow View Post
              2) cutting off I/O barbs of AM1000. I know you've done this successfully, I believe installing 3/4" fittings on your AM1000. I gather you drilled 3/4" holes in the lid and bottom of the AM1000. Then, did you use plastic weld to fit hard 3/4 PVC to the drilled cap/bottom of the AM1000? Also, from your tank pics (which are fantastic!) I cannot see how water actually exits the 3/4 pvc line? What do you connect your 3/4 pvc from AM1000 to that actually dumps back into tank?
              The line exiting the AM1000 goes straight to the tank (I hope this is what you mean)
              Originally posted by growitnow View Post
              3) If I fit the AM1000 with 5/8" barbs, should I retain the same 635gph pump. Or get a bigger one.
              The pump should be enough. My setup has two 450 gph pumps, but my tank is twice as big.
              Originally posted by growitnow View Post
              4) At the tank return side (as per my diagram), my 5/8" ehiem hose is connected to 1/2" loc-line. Will increasing the size of I/O holes in the AM1000 increase output if I retain the 1/2" loc-line output fixtures? Or should I fit the 5/8" eheim hose out of the AM1000 to new 3/4" loc-line fixtures and get rid of the 1/2" loc-line?
              Every 1/2 inch inner diameter will form a bottleneck in the system. The pumps we use a not very strong. They can't develop very much flow under backpressure.

              regards,
              dutchy
              regards,
              dutchy.

              My 2011, 2012 and 2013 AGA aquascaping contest entries:
              http://www.barrreport.com/album.php?u=21013

              Comment


              • #8
                Hi,

                re: efficiency & false gas valve.
                dutchy you are totally correct. My first 5lb CO2 tank lasted >3months; I replaced that CO2 tank and opened the false gas valve - the replaced 5lb tank lasted 1 month. I just put on a 20lb CO2 tank. I know I am wasting CO2, which I'd like to minimize. Right now the goal is to get CO2 levels up. Cranking the needle valve up more from here seems way overkill, in terms of bubble rate that I see others using. Which is why I'm trying to figure out what I'm doing wrong aka "what do I do now?".

                re: how your (dutchy) 3/4 pvc exit the tank. Sorry, I meant what are the actual plumbing bits you connect to the pvc line where water is returned to tank. Do you use loc-line, if so, how do you connect the loc-line to pvc, and what is is that actually hangs over rim of tank (what are the plumbing pieces). I ask because right now my 5/8" ehiem tube going back to tank connects to an eheim installation kit. A loc-line fitting fits beautifully onto the exit end of the ehiem installation kit. But if I follow your route (with 3/4" I/O at reactor), I would have to figure out what to connect to the 3/4" pvc to that actually dumps back to tank.

                scottward: thanks, great questions. Over the break-in period lighting was increased from 8hrs with no mid-day burst, to 10hrs total with 1hr 220w. Your follow up makes sense, I think I will skip the 220w blast altogether, and just run 4.5hr rear bank (110w) followed by 4.5hr front bank (110w), with no burst. [Until recently I had a 10hr total period, just changed to 9hr].

                re: ferts - ferts are on quite heavy EI already (I think)

                re: temp and other changes.
                I live where it gets right some hot in summer, and coldest water temp out of tap is about 81degrees, things have begun to cool down. Tank was set up in June. Ran 3month with no algae except tidbits of GSA. Then GSA got much more prominent & hair algae appeared. Now GSA and hair algae keep "coming back".

                Other things that changed is I have done pruning. Pulling out the H. corymbosa angustifolia & replanting tips. After the first major prune (WOW was there a lot of green!), I have maintained a less dense planting than at set up - though I would figure that to make CO2 MORE available to other plants. I tried Heteranthera zosterifolia and it completely wasted. Blyxa loses base stem and attaches to substrate by root only.

                I have changed filters 1x, added purigen & zeolite & carbon. I have not vacuumed.

                I have been going heavy on excel (45ml daily, the full "water change dose"), I will ease up. I killed some beautiful huge clumps of needle leaf java fern I got from Jeff of GLA by spraying a 50/50mix of excel&water. I have a 'black' thumb!

                Comment


                • #9
                  Originally posted by growitnow View Post

                  re: efficiency & false gas valve.
                  "what do I do now?".
                  !
                  Close the false gas valve. Modify the AM1000. If you can get more flow, you will be able to dissolve more CO2. Avoid restrictions, T's and sharp bends. Get a good 4 dKH drop checker.

                  Originally posted by growitnow View Post
                  Sorry, I meant what are the actual plumbing bits you connect to the pvc line where water is returned to tank.
                  From the reactor outlet the hose makes a nice gradual 180 degree bend upwards to the tank and is connected to black JBL standard filter pipes. On one side the water exits right in the path of a powerhead, to spread out the CO2 enriched water better.
                  That's all, very simple actually.

                  regards,
                  dutchy
                  regards,
                  dutchy.

                  My 2011, 2012 and 2013 AGA aquascaping contest entries:
                  http://www.barrreport.com/album.php?u=21013

                  Comment


                  • #10
                    dutchy, many thanks.

                    btw, I have two drop checkers 4 dKh. Each in the green zone. I just refreshed solution today and put one in the flow of CO2 output, and one low in tank not in flow - to see if the one in the co2 flow actually gets yellow or stays green.

                    JBL seems a European item. There are tank returns in US of course but none that seem to nicely fit 5/8 [except for eheim install kit] or 3/4 [I can't find any, that is]. So I was wondering how folk around here actually plumb their outputs.

                    cheers,
                    growitnow

                    Comment


                    • #11
                      Well, a drop checker being green, doesn't say that much. You could have just 20 ppm. Try to increase CO2 until it touches light green to yellow at the end of the day. Keep an eye on your fish though.

                      The Blyxa surely is a sign of low CO2, so you could try to fine adjust CO2 and wait some time after each adjustment. See how the Blyxa does, that's your best test.

                      regards,
                      dutchy
                      regards,
                      dutchy.

                      My 2011, 2012 and 2013 AGA aquascaping contest entries:
                      http://www.barrreport.com/album.php?u=21013

                      Comment

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