KMattingly Posted May 27, 2002 Report Share Posted May 27, 2002 I have been all around different forums and i asked many questions about a diy mix and how much co2 should be added to a tank. It's a 75 g and most replys have been that only one bottle of mix will not be enough to creat the effect of pearling.They say that I should run 2 bottles of mix to see any effect. Ok, my question is, could i run 1 bottle and have more than 1 bubble per second, say 2, nearly 3 per second, and still be able to have the pearls take off. The bubbles are being chopped up thru a canister filter. Quote Link to comment Share on other sites More sharing options...
Warren Posted May 27, 2002 Report Share Posted May 27, 2002 Hi Kevin, What do you mean by pearling? I've not used a DIY mix, only gas cylinders so I know nothing about them. I'd expect however that you could use a bigger bottle with a larger mix if you want more CO2. If by pearling you mean oxygen bubbles forming on the leaves of the plants, you will also have to have the correct lighting. Just adding more CO2 will not create oxygen bubbles if the lighting is too weak, - the two must be balanced. A little experimenting will be required also. Depending on the type of lights (colour spectrum) you may need more intense lighting (Watts per Litre) if the colour spectrum is not ideal. Quote Link to comment Share on other sites More sharing options...
KMattingly Posted May 27, 2002 Author Report Share Posted May 27, 2002 Pearling is what the other forums call the effect of o2 expelling from the leafs of the plants. That was a good guess!! My lighting is low on watts for a 75, around 70 below the 2 watt per gallon solution. My lights are around 2 months old and are, 1, 48 inch 40 watt coralife bulb, at 10,000 k. 2, 24 inch, spectra max, 20 watt bulbs. All 3 are full spectrum. Most of the plants that i have are the crypt varity and I believe they are a moderate light plant. I also have 3 swords, but they are always green and it does not matter to me if they produce pearls, o2. I have been running the diy mix for 3 days now with no pearls, but i would say that they grew at least 1/4 inch in them 3 days. Although i am in need for a water change. Then do ya think that if i ran with a slow bubble count that with my low lights I may be able to see the pearls. I have seen them one time after I first discovered the diy mix method. The first 4 hours were a don't leave the tank moment. It was like watching a good movie in a theater. After that i have never seen the effect again, after 3 years of messing around with different set ups,SO Quote Link to comment Share on other sites More sharing options...
Warren Posted May 27, 2002 Report Share Posted May 27, 2002 I've only ever seen bubbles on my amazonicus and bleheri sword plants, but not that many. The crypts don't ever seem to do it, probably because they grow so slow. I get 1 new full sized leaf every 2 days on most of my sword plants. On the osirus it starts off deep red and gets about 5 inches long on day 1 and continues to 10 inches turning green/red on day 2. The amazonicus starts off red/green and ends up green with some bubbles on the top half of the leaves. Cobomba piauhyensis grows about 5 inches a day and gets heaps of bubbles on it. So does Bacopa caroliniana and Rotala macrandra (as well as being bright red). These two only grow about 1 inch a day. Sometimes there are a few bubbles on the Glossostigma and tenelus. Your light intensity is probably too low to get much. With the type of plants you have, more light may promote algae. If all is growing well with little or no algae, I wouldn't worry if there are no bubbles. Many of my plants do not bubble either and they grow very quickly. I'm using 8 x 5 foot 58 Watt Colour96 Daylight tubes. They are 6500K white light with very high natural colour rendering. Its not a lot of watts, about 1.54 per gallon, but the tubes have a very high lumen output compared to many others (about double). All that matters is it works. Quote Link to comment Share on other sites More sharing options...
KMattingly Posted May 27, 2002 Author Report Share Posted May 27, 2002 My amazon swords do the same leaf growth,they grow well except for the ocational decaying of the leafs. I'm guessing that it's old age and the plant decides that it's time to let that leaf go? I don't know. As for the overall tank health, I have great numbers and very low fish death, plant death. You are right all that matters is it works. Thanks Warren!! Quote Link to comment Share on other sites More sharing options...
john1 Posted July 29, 2002 Report Share Posted July 29, 2002 Hi KMattingly I posted something about co2 somewhere in the technical side. According to a german site the formula is aquarium liters X 13 / 100. Gives you bubbles per minute. That is definately something to start with. Quote Link to comment Share on other sites More sharing options...
Derek Posted July 29, 2002 Report Share Posted July 29, 2002 Hi John, A formulae for determining bubble frequency would be handy to determine a starting point. But I have a problem with such a simple formula, as given. Other factors aside for now, did this site mention the size of bubble? Did it also mention if it was refering to a DIY yeast produced CO2 or CO2 from a gas cylinder? Obviously the size of bubble relates to the amount of gas available to be dissolved in the aquarium water. The source of CO2 also relates to the amount of gas available as the % of CO2 in the gas mixture varies between these two sources. Without these factors (as well as others) the formula; number of bubbles = aquarium liters X 13 / 100 is meaningless. For example, say I have a 100litre aquarium, how does "knowing" I have to add 13 bubbles of CO2 help me. I'm not getting at you, but I do have a problem with this formula. Quote Link to comment Share on other sites More sharing options...
john1 Posted July 29, 2002 Report Share Posted July 29, 2002 Hi Derek The formula is from a very reputable company. Bubbles can differ in size. Think about it SERA, DUPLA and quite a few other sell BUBBLE COUNTERS!! The formula IS a good starting point. Provided you know the size. Let's face it, if you use an inch hose the bubble is bigger than a standard airhose. I do not know the exact science of it because I actually only started to buy the gasbottle and regulator (cheap). I actually also tried a yeast bottle and used an ordinary airhose to produce the bubbles. IT WORKED. If you are serious about co2 then you should get an co2 indicator. (DUPLA DAUERTEST) For argument sake you get a 10 l tank. Use the formula. Observe the co2 indicator. That should be also a good starting point. Greetings my friend John Quote Link to comment Share on other sites More sharing options...
Derek Posted July 30, 2002 Report Share Posted July 30, 2002 Hi John if you use an inch hose the bubble is bigger than a standard airhose. Quote Link to comment Share on other sites More sharing options...
Derek Posted July 30, 2002 Report Share Posted July 30, 2002 Getting back to Kevin's original question. That initial burst of "pearling" suggests that you had conditions (if only for 4 hours) that supported that degree of photosynthesis. You should be able to recreate those conditions. The most likely senario (or at least the one I would look into first) is that prior to adding the CO2 your plants growth was limited by the available concentration of CO2. Once you corrected this by adding CO2 another factor became rate limiting. The most likely factor(s) is/are one of the micro nutrients. Do you use any supplemental fertilization of the water column in your tank? Quote Link to comment Share on other sites More sharing options...
john1 Posted July 30, 2002 Report Share Posted July 30, 2002 Hi Derek Here is the answer you are probably looking for. The bubble size should be 1/8" (3mm) I just tested my D.I.Y. CO2 set-up. Bubbles about 1/8" with a hose (pipe) which is smaller than an ordianary airhose. Then I tried a smaller pipe the bubblesize decreased by half. Which might not be enough to supply a 3" tank. BUT THIS IS ONLY A STARTING POINT!! BFN John Quote Link to comment Share on other sites More sharing options...
Warren Posted July 30, 2002 Report Share Posted July 30, 2002 How is the CO2 added to the tank? Is it bubbled in from the bottom, or is a gas reactor of some sort used. I use a DIY gas reactor. 100% of the CO2 is dissolved into the water if the gas reactor is good enough. The bubbles per minute is useless unless it is specified for a certain bubble size and only if 100% of the CO2 if dissolved and only if the gas is 100% CO2. Anything else and more CO2 (or gas) will be required, - just how much who knows? Its a reasonable starting point but ... Quote Link to comment Share on other sites More sharing options...
john1 Posted July 30, 2002 Report Share Posted July 30, 2002 Warren You are right. If you hang an airhose in the water and it bubbles the 'correct' amount of bubbles does not mean the water gets the correct amount of CO2. As I said before, it is only a starting point. I WILL get a diffusor,reactor, atomizer or whatever is required to get it going. I cannot let a full bottle of CO2 into the tank in 10 minutes. Apparently kills the fish. HE HE. I have in mind, correct me please if I'm wrong, after all I' pretty new in CO2 ing, to get the SERA basic set to which I connect my bottle, regulator, needlevalve. Then I get the DUPLA DAUERTEST indicator. ANY critisism is welcome. John Quote Link to comment Share on other sites More sharing options...
cees Posted July 30, 2002 Report Share Posted July 30, 2002 ... how much co2 should be added to a tank. ..... .... Ok, my question is, could i run 1 bottle and have more than 1 bubble per second, say 2, nearly 3 per second, and still be able to have the pearls take off. ideal conditions, add enough CO2 to maintain a pH of 7 at a kH (carbonate hardness) of at least 4 dH, it's that simple. Than you know that CO2 is not limiting. Most likely it'll be light that will be limiting, fix that and micronutrients go, fix that and before you know it you'll be adding, yes adding!, potassium nitrate because you are getting into nitrate deficiency problems. If you get that far you'll be supplying a lot of people with a lot of plants. Do regular water changes. Oh, and did I mention it, add a lot of fast growing plants. Having ideal growing conditions but not enough plants is asking for trouble. Not sure about your CO2 bottle size but a common size bottle (50 cm heigh?, can't remember the code now) should last you a year if not longer on a 70g tank (is that gallon?) CO2 tester, if you can, get one of those dupla 'divebell' testers see http://www.dupla.com/e008.htm At the UHAS club a few years ago I actually made a few myself from a 10 mL glass bottle with cap and a piece of airline tubing. Works well, problem is to make the holder to stick it to the glass. Never got a satisfactory solution for that, but than again I didn' need to, I had a dupla tester. The dupla indicator is I believe a 'mixed indicator' but bromo-thymolblue will do. Some pet-shops actually have it. It's a pH sensitive indicator at with color change blue/yellow at about 7. Quote Link to comment Share on other sites More sharing options...
Ira Posted July 30, 2002 Report Share Posted July 30, 2002 Hehe, Speaking of potassium nitrate, I've actually got a little 500 gram container of it sitting right here next to my computer. $8 at your local garden center. I've elminated it from the fertilizer mix I use though. Isn't there a way to directly measure CO2? There must be. Or is all the ways more laboratory type methods and not really suitable? Someday we'll just have a little box that plugs onto your filter and reads off every stat you could think of... Quote Link to comment Share on other sites More sharing options...
Derek Posted July 30, 2002 Report Share Posted July 30, 2002 If you hang an airhose in the water and it bubbles the 'correct' amount of bubbles does not mean the water gets the correct amount of CO2. As I said before, it is only a starting point Exactly and as I have been pointing out this makes the formula you gave (without any other criteria) absolutely meaningless. Any figure could be a "starting point". I just tested my D.I.Y. CO2 set-up. Bubbles about 1/8" with a hose (pipe) which is smaller than an ordianary airhose. Then I tried a smaller pipe the bubblesize decreased by half. Which might not be enough to supply a 3" tank. If you created bubbles 1/2 the size, then in theory, they should have been coming out of the tube 8x as fast. The DIY generator makes the same amount of CO2 per minute regardless of the tubes diameter. In fact the smaller bubbles may even increase the amont of CO2 dissolved in the water. This assumes that your reactor is not 100% efficient and the fact that a smaller bubble presents a larger surface area per volume than a large bubble does. Consequently more CO2 can de dissolved during the time the bubble is in contact with the water. Make sure you read up about the relationships between CO2 concentration, ph and KH before blindly relying on the "DUPLA DAUERTEST indicator" A good start would be http://www.thekrib.com/Plants/CO2/ Cees has given a much better "starting point" when he describes ideal conditions than any formula simply relying on a count of bubbles ever will. Quote Link to comment Share on other sites More sharing options...
cees Posted July 30, 2002 Report Share Posted July 30, 2002 Hehe, Speaking of potassium nitrate, I've actually got a little 500 gram container of it sitting right here next to my computer. $8 at your local garden center. I've elminated it from the fertilizer mix I use though. Only add if your nitrate levels, properly measured, are 0 ppm and you are absolutely certain that everthing else is perfect and you can see signs of nitrate deficiency in your plants (can't remember what they are now). Isn't there a way to directly measure CO2? There must be. Or is all the ways more laboratory type methods and not really suitable? Someday we'll just have a little box that plugs onto your filter and reads off every stat you could think of... hmmmm, measure pH, measure kH (but how realiable is that) read the chart (see link by Derek). Much better way, observe your plants, observe your fish, are they healthy, are they growing, is algae growth at acceptable level, am I happy with my tank. If the answer is yes then I suppose that the levels of whatever I'm supposed to measure much be good. Now, if you want instant something (and keeping fish/plants in a tank isn't like that) I'm sure there will be lots of people who are happy to take your $$ and sell you testkits, measuring gear etc etc etc etc ... sorry, thinking out loud again read the book 'optimum aquarium' by the Dupla people (if you read Dutch I can lend you my copy) to understand the philosophy of it. Read the discussions on the aquatic plant list (link anyone?). Than decide for yourself what you are going to do about that planted tank is it going to be a) traditional no fuss b) all out technical and $$$ or c) your own thing trying to achieve your optimum at a budget. Quote Link to comment Share on other sites More sharing options...
Derek Posted July 30, 2002 Report Share Posted July 30, 2002 Link for the aquatic plant list http://fins.actwin.com/aquatic-plants/ Quote Link to comment Share on other sites More sharing options...
Pegasus Posted July 30, 2002 Report Share Posted July 30, 2002 I'm just smiling to myself here. This hobby seems to get more complicated by the minute. Now where is that Dutch translation book I had :) Sorry to be a PITA, but shouldn't this topic be in Technical... or Aquatic Plants even. I think I may have asked this question before somewhere. Bill. Quote Link to comment Share on other sites More sharing options...
Pegasus Posted July 30, 2002 Report Share Posted July 30, 2002 Come on you guys. Find an appropriate area before you make your posts. This one has been moved from FRESHWATER. You're frightening all our new members away Moderator. Quote Link to comment Share on other sites More sharing options...
john1 Posted August 4, 2002 Report Share Posted August 4, 2002 Hi Ira Yes, there is. It's called DUPLA Dauertest. German for "all the time" It shows you 'green' for ok and two other colours for 'not enough' and 'too much'. Cost according to Dupla Adalaide $37.00 John Quote Link to comment Share on other sites More sharing options...
john1 Posted August 23, 2002 Report Share Posted August 23, 2002 I just bought a co2 tester from VITAKRAFT. According to the test kit my co2 concentration is 6.5ppm. According to my formula which ALL charts are based upon it has 30 ppm. So something seems to be wrong with the testkit OR my way of measuring!!! I sent an e-mail to the company to find out. John PS the formula is CO2= 3 x dKH x 10^(7-pH). And it is correct. Quote Link to comment Share on other sites More sharing options...
Derek Posted August 23, 2002 Report Share Posted August 23, 2002 Hi John, Yes, the formula is correct but there is one uderlying principle that it relies upon. That is that all the of the alkalinity in your tank water is provided by CO3 / HCO3 ions. Does your test kit specifically measure CO3 / HCO3 or does it measure total alkalinity in the form of carbonate equivalents. If you have additional buffering system(s) present in your tank water ( in addition to CO3 / HCO3 ) that do not affect dKH but do contribute to alkalinity and also affects pH such as a phosphate buffer then the tables you refer to and the formula that they are derived from will no longer apply. Another way of putting it: dKH measures total akalinity not just CO3 / HCO3 ions while the formula is based on the concentration of CO3 / HCO3 ions only. So when you put the total alkalinity of the water (in CO3 eqivalents) into the equation at a known pH you will calculate an inaccurate and higher CO2 concentration. Quote Link to comment Share on other sites More sharing options...
john1 Posted August 23, 2002 Report Share Posted August 23, 2002 Hi Derek Thanks. you say"Does your test kit specifically measure CO3 / HCO3 or does it measure total alkalinity in the form of carbonate equivalents. " ??? I don't know. I use an electronic pH meter. Apart from the CO2 tester all others are from Aquarium Pharmaceutical Inc. A quick rundown. Ammonia 0.00 Nitrate 0.00 Nitrite 0.00 pH 6.8 dKH 3.5 after adding 2 lots!!!! of KH Powder (Betta) CO2 11 ppm Thanks John PS Let me know what I do wrong :oops: Quote Link to comment Share on other sites More sharing options...
Derek Posted August 24, 2002 Report Share Posted August 24, 2002 Hi John, You are not doing anything wrong it is just that your formula relies on the alkalinity in your tank water be composed entirely of CO3/HCO3 and it appears that this is not the case in your tank water. I know nothing about Betta KH Powder, I suspect it is probably just very expensive baking soda. Another formula you could try is log(CO2) = pH(a) - pH(t) - 0.3. Where: pH(a) is the pH of your tank water after it has been aerated ( i.e. shake the sample vigorously until the pH climbs and remains CONSTANT. The CO2 content should be in equilibrium with the air at this point) and, PH(t) is the pH of your tank water For example the pH of your tank water is 6.8 = pH(t) If after aerating this water the pH rose to 8.0 = pH(a) Then log(CO2) = 8.0-6.8-0.3 = 0.9 Therfore CO2 in ppm = is 10^(0.9), or about 8 ppm. This formula attempts to get around the interference that buffers other than CO3/HCO3 contribute to the formula that you are presently using. A fuller explanation can be found at http://www.thekrib.com/Plants/CO2/kh-ph-co2-chart.html Hope this helps. Quote Link to comment Share on other sites More sharing options...
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