Depends on the cv (coefficient of flow) of the needle valve. The lower the Cv the more turns you need to do to increase flow. The Swagelok M series has an 0.056mm orifice with a 0.03 Cv while the S series has a 0.032mm orifice with a 0.004 Cv.What @Hanuman was also talking about with me ( on one of our phone calls) is the cheapo needle value are not just hyper sensitive they are also unreliable, one day they give you one pH drop the next its another, this this my be related to small temp changes can have a dramatic effect on needle valves also, the cheap needle valves are better suited to high flow and are being used for low flow as they are cheap, Yes you can get lucky but the slightest movement of the needle valve and it does a different injection rate. The needle valves Hani has got (correct me if I am wrong m8) have to be turned say 90 degrees to increase from 6bps to 7 bps and not the slightest touch goes from 6BPS to 20BPS
I think these Swagelok orifice sizes are actually inches, not mm ( www.swagelok.com/downloads/webcatalogs/en/MS-01-142.pdf ) so the S-series is 0.032" (0.81 mm) with a 0.004 Cv. I picked up a second hand Hoke Micromite 1600 series (model 1656g4ya: Item # 1656G4YA, Micromite 1600 Series On Hoke Inc. ) with a 0.031" (0.79 mm) orifice and a 0.0008 Cv which I thought would do the trick but was disappointed with it. Maybe mine is defective but I get better performance at really low flow rates from this cheapo £22.50 model from Amazon ( www.amazon.co.uk/gp/product/B07TSHVX6B ). I have them hooked up in series which did help. For me anyway, adding a flow restrictor was the big difference maker where now I leave the Mircomite open (afraid to take it out of the inline setup in case things start leaking gas when I mess with it). I confess to not having the physics expertise to understand how to use these parameters to calculate real-world flow rates so there was a certain amount of "try it and see" and to be fair, with a 45 L tank I do need really low CO2 injection flow rates.Depends on the cv (coefficient of flow) of the needle valve. The lower the Cv the more turns you need to do to increase flow. The Swagelok M series has an 0.056mm orifice with a 0.03 Cv while the S series has a 0.032mm orifice with a 0.004 Cv.
No I haven't, at least not yet. I have managed to get both diffusers running at 60 BPM which is an increase of 20 BPM on each diffuser. So 120 BPM now. I am going to leave it alone now and reassess in a weeks time.Have you tried balancing the splitter so it’s even and controlling the bpm on the regulator?
Hi Clive,Thank you for the additional data. This is mistake #1. The holes in the spraybars should be angled upwards ever so slightly.
This is mistake #2. Any auxiliary pumps being used must supplement the output energy of spraybar by being place as closely as possible and directly below the spraybar at the midpoint of the spraybar length and should not be angled.. When the pump is place so far below the spraybar, it's effect is to actually cancel the energy of the spraybar flow by interfering with the flow coming down the front glass.
This is impossible. It must be that you are reading the pH of the tank and then are using this reading in a pH/CO2 chart, which is the worst thing you can possibly do. The pH/KH/CO2 chart was never meant to take direct readings from a tank. The chart assumes that the only source of acid in the water is due to carbonic acid. Tank water has lots of other acids that disrupt the pH reading and almost always results in underestimating the CO2 content. Likewise, tank water should NOT be used in the DC. the pH/KH/CO2 chart will function perfectly only if the water inside the DC is distilled water adjusted to 4dKH, otherwise the reading is meaningless.
I now understand the nature of the difficulty. I suggest you make the adjustments to the flow/distribution via re-positioning and re-orientation of the pump/spraybar. It's still unclear how the diffusion is accomplished but one solution is to place the diffuser under the filter inlet in order to use the filter as the diffuser. You should also consider removing about 2/3rds of your filter media, assuming you have it filled, as most of the media is unnecessary and it penalizes flow throughput. This will make your FX5 much, much more efficient.
Cheers,
Hi Nigel,Hi Clive,
Sorry to jump on someone's post, but I believe from your response, I'm doing 2 incorrect things.
1) I use normal tap water in dc. Should I boil and let cool first?
Yes, the powerhead must supplement the energy of the spraybar. it's energy will pull the spraybars energy along to help get the water to the opposite glass, where it will be deflected downward. When water (or any fluid or object for that matter) has to change direction it loses energy. we are trying to send the water down the front glass where it has to change directions again by heading towards the back and then it must change directions again where we want it to climb up the rear wall. That's a LOT of energy loss, so the purpose of the pump is to act as a booster rocket, so it must send it's energy in exactly the same direction and must match, as closely as possible the energy vector of the spraybar.2) Are show saying additional powerhead should be on back wall just under spray bars
Not sure if I have missed the point
Hi,yes I fully agree with your point. I simply happen to know from experience, based on the size of the tank, that the 8 or 9 or 10 bps will never make the grade. We also happen to know anecdotally that blue DC is not good and that a bright lime green is the goal, especially in these days of overpowered lights. So the situation is not as vague as one might imagine. We have lots of other guides which provide the rules of thumb, yet, as you say, the finer points are not always understood.These factors are all related and solved together - not linearly. So you wouldn't determine the injection rate first then fix flow/distribution because one determines the other. Surface movement, depth at which co2 is introduced, method etc. all affect the rate and will give a more precise result - so 8 is not enough but what is? 9? 15? 20? Should we always try to go for green in the dc? What about blue green? What if just blue? Surface movement effects may not factor in the solution, but is part of the problem and should be understood. Testing in order to determine the relationship in more depth before determining the solution is important - as some comments in the sticky have suggested. Not doing so is one of the reasons why there are still so many posts of people concerned about gassing their fish or not knowing the colour of dc to aim for, even as they try to address flow.
I am not saying your solution will not address OPs issue - just that evaluating the issue should be part of it and that can lead to other solutions.
Well, here's the thing: You really want to optimize your CO2/flow/distribution first and foremost. The penalty you may pay in the short term is to damage a few boards, but what you learn from implementing the procedures is worth more than a few boards. After you are able to optimize the behavior of the gas you can then make slight tweaks to determine how far you can stray from the "ideal" and still be within the correct regime. So yes, you can "get away" with lowering the spraybar slightly, but if you lower it too far you will be forcing water to climb up the opposite pane as well as getting some of it to go down. The surface of the water acts as a kind of barrier forcing the water to mostly flow down. If there is too much splashing for your taste then instead of angling the holes up, just try to keep them at the horizontal (level).should I lower the spray bar so I can angle it up more?
OK, cool. Thanks for the explanation. That diffuser seems OK and getting rid of some media will do wonders for your flow throughput and distribution.Diffusion is done on the filter outlet with a filterless water filter housing and brass fittings. The water flows backwards through its normal use with a tube making the water come out at the bottom of it to adjust ate the co2 to help it diffuse.
I’ll also remove some of the media and spread it out within the trays more.
Correct. I'm metric biased. Hate inches. My brain unconsciously inverted the units.I think these Swagelok orifice sizes are actually inches, not mm
Thank you so much for your detailed response Clive. I've learnt two super things today and I can't wait to see the difference in moving the powerhead..Makes total sense, cheers mateHi Nigel,
The DC should be filled with distilled or RO water adjusted to 4dKH only. Tap water will have impurities that will currupt the readings. 4dKH water is sold by our sponsors as well as other on-line establishment. If you want to prepare it yourself you can just buy the distilled water and add carbonate salt measured out with an accurate scale, but it's so easy to find 4dKH water (or at least it should be). No substitute is acceptable.
Yes, the powerhead must supplement the energy of the spraybar. it's energy will pull the spraybars energy along to help get the water to the opposite glass, where it will be deflected downward. When water (or any fluid or object for that matter) has to change direction it loses energy. we are trying to send the water down the front glass where it has to change directions again by heading towards the back and then it must change directions again where we want it to climb up the rear wall. That's a LOT of energy loss, so the purpose of the pump is to act as a booster rocket, so it must send it's energy in exactly the same direction and must match, as closely as possible the energy vector of the spraybar.
Cheers,
Hi Nigel,
The DC should be filled with distilled or RO water adjusted to 4dKH only. Tap water will have impurities that will currupt the readings. 4dKH water is sold by our sponsors as well as other on-line establishment. If you want to prepare it yourself you can just buy the distilled water and add carbonate salt measured out with an accurate scale, but it's so easy to find 4dKH water (or at least it should be). No substitute is acceptable.
Yes, the powerhead must supplement the energy of the spraybar. it's energy will pull the spraybars energy along to help get the water to the opposite glass, where it will be deflected downward. When water (or any fluid or object for that matter) has to change direction it loses energy. we are trying to send the water down the front glass where it has to change directions again by heading towards the back and then it must change directions again where we want it to climb up the rear wall. That's a LOT of energy loss, so the purpose of the pump is to act as a booster rocket, so it must send it's energy in exactly the same direction and must match, as closely as possible the energy vector of the spraybar.
Cheers,
Hi Clive, just repositioned powerhead and extended spraybar. Plenty of gaseous exchange once I replace co2 bottle. Does this look better do you thinkHi Nigel,
The DC should be filled with distilled or RO water adjusted to 4dKH only. Tap water will have impurities that will currupt the readings. 4dKH water is sold by our sponsors as well as other on-line establishment. If you want to prepare it yourself you can just buy the distilled water and add carbonate salt measured out with an accurate scale, but it's so easy to find 4dKH water (or at least it should be). No substitute is acceptable.
Yes, the powerhead must supplement the energy of the spraybar. it's energy will pull the spraybars energy along to help get the water to the opposite glass, where it will be deflected downward. When water (or any fluid or object for that matter) has to change direction it loses energy. we are trying to send the water down the front glass where it has to change directions again by heading towards the back and then it must change directions again where we want it to climb up the rear wall. That's a LOT of energy loss, so the purpose of the pump is to act as a booster rocket, so it must send it's energy in exactly the same direction and must match, as closely as possible the energy vector of the spraybar.
Cheers,
Hi Clive, just repositioned powerhead and extended spraybar. Plenty of gaseous exchange once I replace co2 bottle. Does this look better do you think
Thanks Nigel
Hi Nigel,Hi Clive, just repositioned powerhead and extended spraybar. Plenty of gaseous exchange once I replace co2 bottle. Does this look better do you think