Well i took some of advice from you guys and got another power head, i have 1 maxijet 400 and 1 maxijet 900. would this be enough flow for the tank, my goby seems to be doing fine in the flow, there are some places he wont go to though, my zoas are the happiest they have ever been! and so are my green star polyps, but my ricordia is smaller than it usualy is. i have about 35 turn over in a ten gallon, does this seem like enough?
Enough flow???
- Thread starter ram man
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Seems like a good amount of water flow. Generally mushrooms/ricordia don't like that strong of a flow, but your other coral will benefit from the added circulation and flow. I know in my nano I have a very strong powerhead (some generic that I have no clue what it is) with a spray bar outlet, along with a small mini-jet pump.
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This is the same question that I have asked in many different forms and have never got an adequate/definite answer from anyone. The water turn over should not anyway effect the corals. Now, on the other hand, flow rate within (created by power heads or spray bars or etc) tank will definitely have an effect on your corals. 15 to 20 times the turn over is what many recommend for a reef tank. But more is always better. As far as I am concerned this (turn over) is completely different from flow rate.
In my 70gal tank I have about 21 times turn over (combine from canister filter and wet/dry pump); not counting the powerheads. But I feel that lack or inadequate flow rate within the tank i.e. water movement similar to the conditions in the ocean. I hope to buy, either a better power heads or create wave make from powerful water pump. That is for the future.
I hope someone either verofy my theory or explain this better.
Rohn
In my 70gal tank I have about 21 times turn over (combine from canister filter and wet/dry pump); not counting the powerheads. But I feel that lack or inadequate flow rate within the tank i.e. water movement similar to the conditions in the ocean. I hope to buy, either a better power heads or create wave make from powerful water pump. That is for the future.
I hope someone either verofy my theory or explain this better.
Rohn
How are you defining turnover wrt flow. Turn over can be included in flow as it involves water going out ofthe tank and reentering in a different place (thus meaning movement). Normally though turnover thro' the sump is not a big part as to get 25 times turnover thro' a sump would mean a lot of problems for most sumps.
Can you please try to explain what you mean, and also give a list of what hardware you have.
Also you might want to consider the difference between a cannister and a 'closed loop'. Instead of powerheads, which in it's crudest form is a pipe going out of the tank to a big pump, pushing the water back in. Well a cannister is effectively the same (though almost always smaller), but with a bit of filtration popped in the middle.
I would agree that compared to the ocean 21 times is weeny flow
Can you please try to explain what you mean, and also give a list of what hardware you have.
Also you might want to consider the difference between a cannister and a 'closed loop'. Instead of powerheads, which in it's crudest form is a pipe going out of the tank to a big pump, pushing the water back in. Well a cannister is effectively the same (though almost always smaller), but with a bit of filtration popped in the middle.
I would agree that compared to the ocean 21 times is weeny flow
Turn over : From what I understand turn over is the amount of water that leave the tank and re-enter after passing through come kind of a filter or water that just leave the tank and re-enter the tank.
Flow rate: This is the actual water movement in your tank.
Suppose, you have 55 gallon tank with canister filter that is rated at say 2750 GPH. This mean that you have 50 time turn over. Water leave the tank and re-enter at rate of 2750 GPH … 50 times the volume of the water. This doesn’t necessarily mean that entire volume of water in your tank is turned over 50 times. It simply mean 2750 gallon of water moved through the system (disregard head loss or any other loss … theoretically). But my tank may have many dead spots.
To prevent dead spots you place a few power heads in the tank. To me this flow rate … how fast the water is moving … i.e. current.
So in my mind, water simply turning over number of times does create a current within the tank. Having powerhead rated at 2750 GPH alone isn’t enough either. You must strike balance between flow rate and turn over.
Now to my 70 gal tank. I have pump from the sump rated at 1200 GPH and fluval canister filter rated at 317GPH. This is about 21 times turn over (theoretically). But only have couple of 505 powerhead on either end of the tank. If I were to place my hand on the middle of the tank, I feel absolutely no current. This is why I feel that my tank as inadequate flow rate, yet enough turn over. Now, I have an extra pump that I can use to create a close loop. But this would only increase turn over and not increase flow rate or remove dead spots. What is my best option?
Sorry if I hijacked this thread. I hope I get better answer this time.
Rohn
Flow rate: This is the actual water movement in your tank.
Suppose, you have 55 gallon tank with canister filter that is rated at say 2750 GPH. This mean that you have 50 time turn over. Water leave the tank and re-enter at rate of 2750 GPH … 50 times the volume of the water. This doesn’t necessarily mean that entire volume of water in your tank is turned over 50 times. It simply mean 2750 gallon of water moved through the system (disregard head loss or any other loss … theoretically). But my tank may have many dead spots.
To prevent dead spots you place a few power heads in the tank. To me this flow rate … how fast the water is moving … i.e. current.
So in my mind, water simply turning over number of times does create a current within the tank. Having powerhead rated at 2750 GPH alone isn’t enough either. You must strike balance between flow rate and turn over.
Now to my 70 gal tank. I have pump from the sump rated at 1200 GPH and fluval canister filter rated at 317GPH. This is about 21 times turn over (theoretically). But only have couple of 505 powerhead on either end of the tank. If I were to place my hand on the middle of the tank, I feel absolutely no current. This is why I feel that my tank as inadequate flow rate, yet enough turn over. Now, I have an extra pump that I can use to create a close loop. But this would only increase turn over and not increase flow rate or remove dead spots. What is my best option?
Sorry if I hijacked this thread. I hope I get better answer this time.
Rohn
Hi - I'll do a bit of cut and paste and try ot make sense. the basic issue is that measuring current per se is very difficult to do in aquaria, so people use turnover as a rough approximation, but as you are seeing it is a rough approximation.
Turn over : From what I understand turn over is the amount of water that leave the tank and re-enter after passing through come kind of a filter or water that just leave the tank and re-enter the tank <<AND/OR the amount of water moved by a powerhead>>
Flow rate: This is the actual water movement in your tank. <<Umm not really thinking about it, though it could be. As a rate it is a function of time so you could describe flow rate as a current i.e. 30 centimetres persecond. Normally though it is the amount of water a device shifts, i.e. 2000 litres per hour>>
Suppose, you have 55 gallon tank with canister filter that is rated at say 2750 GPH <<Some cannister!>>. This mean that you have 50 time turn over. Water leave the tank and re-enter at rate of 2750 GPH … 50 times the volume of the water. This doesn’t necessarily mean that entire volume of water in your tank is turned over 50 times. It simply mean 2750 gallon of water moved through the system (disregard head loss or any other loss … theoretically). But my tank may have many dead spots <<Indeed. Maximising water movement to avoid dead spots is not always straightforward>>.
To prevent dead spots you place a few power heads in the tank. To me this flow rate … how fast the water is moving … i.e. current. <<You could still have dead spots tho' even if one part of the tank has a hideously high current>>
So in my mind, water simply turning over number of times does create a current within the tank. Having powerhead rated at 2750 GPH alone isn’t enough either. You must strike balance between flow rate and turn over. Substitute the word current for flow rate and I thnk this will be clearer>>
Now to my 70 gal tank. I have pump from the sump rated at 1200 GPH and fluval canister filter rated at 317GPH. This is about 21 times turn over (theoretically). But only have couple of 505 powerhead on either end of the tank. If I were to place my hand on the middle of the tank, I feel absolutely no current. <<Typical>>This is why I feel that my tank as inadequate flow rate, yet enough turn over. Now, I have an extra pump that I can use to create a close loop. But this would only increase turn over and not increase flow rate or remove dead spots.<<Well set it up right>> What is my best option?
<<If you want to get serious about water flow you have options. But remember one thing - squeezing mucho water out of a little hole, even at high flow rates, will not give you good current. The stream is narrow, high velocity and terribly turbulent and typically will have dissipated to not much after 20 centrimetres from the exit. Compare to the stream from a Tunze or Seio - big propellors, big exit holes, lower velocities leaving the pump, but as the 'stream' of water is wider and less turbulent it trvels much, much further. Trad Powerheads were NOT designed to provide currents, in tank flow - they were designed to feed things like powered UGF's UV's, skimmers et al, and their nonoptimised propellor/impellor design reflects this.
Ditto with the closed loop - if you pump all the out flow from one little hole it will be much less effective than more ,larger outlets.
The semi exception to this are eductors, and your tank isn't big enough for an eductor I think, though there are mini version available. Google eductor or use wikipedia for a description.
Turn over : From what I understand turn over is the amount of water that leave the tank and re-enter after passing through come kind of a filter or water that just leave the tank and re-enter the tank <<AND/OR the amount of water moved by a powerhead>>
Flow rate: This is the actual water movement in your tank. <<Umm not really thinking about it, though it could be. As a rate it is a function of time so you could describe flow rate as a current i.e. 30 centimetres persecond. Normally though it is the amount of water a device shifts, i.e. 2000 litres per hour>>
Suppose, you have 55 gallon tank with canister filter that is rated at say 2750 GPH <<Some cannister!>>. This mean that you have 50 time turn over. Water leave the tank and re-enter at rate of 2750 GPH … 50 times the volume of the water. This doesn’t necessarily mean that entire volume of water in your tank is turned over 50 times. It simply mean 2750 gallon of water moved through the system (disregard head loss or any other loss … theoretically). But my tank may have many dead spots <<Indeed. Maximising water movement to avoid dead spots is not always straightforward>>.
To prevent dead spots you place a few power heads in the tank. To me this flow rate … how fast the water is moving … i.e. current. <<You could still have dead spots tho' even if one part of the tank has a hideously high current>>
So in my mind, water simply turning over number of times does create a current within the tank. Having powerhead rated at 2750 GPH alone isn’t enough either. You must strike balance between flow rate and turn over. Substitute the word current for flow rate and I thnk this will be clearer>>
Now to my 70 gal tank. I have pump from the sump rated at 1200 GPH and fluval canister filter rated at 317GPH. This is about 21 times turn over (theoretically). But only have couple of 505 powerhead on either end of the tank. If I were to place my hand on the middle of the tank, I feel absolutely no current. <<Typical>>This is why I feel that my tank as inadequate flow rate, yet enough turn over. Now, I have an extra pump that I can use to create a close loop. But this would only increase turn over and not increase flow rate or remove dead spots.<<Well set it up right>> What is my best option?
<<If you want to get serious about water flow you have options. But remember one thing - squeezing mucho water out of a little hole, even at high flow rates, will not give you good current. The stream is narrow, high velocity and terribly turbulent and typically will have dissipated to not much after 20 centrimetres from the exit. Compare to the stream from a Tunze or Seio - big propellors, big exit holes, lower velocities leaving the pump, but as the 'stream' of water is wider and less turbulent it trvels much, much further. Trad Powerheads were NOT designed to provide currents, in tank flow - they were designed to feed things like powered UGF's UV's, skimmers et al, and their nonoptimised propellor/impellor design reflects this.
Ditto with the closed loop - if you pump all the out flow from one little hole it will be much less effective than more ,larger outlets.
The semi exception to this are eductors, and your tank isn't big enough for an eductor I think, though there are mini version available. Google eductor or use wikipedia for a description.
I don't know because we don't have anything like enough information yet. Getting your water movemetn where you want it to be is not a simple gallon* turnover problem.
1. How does your tank look. How the tank is aquascaped strongly affects how water in the tank moves. If you are bad at aquascaping and jsut have a rockwall along the back, that needs a differnet pump configuration to something that's just a low lying pile of rocks in the middle, or a series of vertical pillars (The latter is the most obstructive to water flow but can be the easiest as they create turbulence)
2. What are you keeping - higher energy sps, sarcophytons, or lower energy lagoon corals. Bear in mind thesr things can grow quickly, thus affecting (almost invariably reducing) the amount of flow.
3. How do you want it to look, what appearance are you after.
As an example my tank has most of it's live rock concenrated in an 'island at one end of the tank, there are two vertical pillars/masses getting to it. At the end with out much rock sits a big tunze powerhead pushing 6000 lph on a timer to provide 6000lph for about 8 seconds, and 2000 -3000lph (depending on how I set it) for 4 secnds inbetween. This effectively pushes waves along the tank that bounce of the front glass and wash over the rock mound. The larger rock pilar is designedto just catch the egge of the flow of water, and uses to turbulen flow to pull a mass of water round and behind it.
To collect debris settling behind the major mass of rock I have a Fluval 4plus with a 3plus body on it I tihnk.
That's it. In your example I would use a closed loop as you already have the pump, and powerheads are a real faff - the ones available in the US all seem to be horribly unreliable,( plus they inevitably have a livestock 'incidnet' mashed anemonae....), and getting them out to clean them can be pain. Plus lots of wires hanging around is a p.i.t.b.
It's good to try to understand what all this means in practicality. Water movement is probably the most vital thing to get right in a tank as it affects your filtration so much. I start with the rule simple is best, and think it's not a bad idea to plan for oversizing this stuff.
Photo of tank would be nice plus other info.
1. How does your tank look. How the tank is aquascaped strongly affects how water in the tank moves. If you are bad at aquascaping and jsut have a rockwall along the back, that needs a differnet pump configuration to something that's just a low lying pile of rocks in the middle, or a series of vertical pillars (The latter is the most obstructive to water flow but can be the easiest as they create turbulence)
2. What are you keeping - higher energy sps, sarcophytons, or lower energy lagoon corals. Bear in mind thesr things can grow quickly, thus affecting (almost invariably reducing) the amount of flow.
3. How do you want it to look, what appearance are you after.
As an example my tank has most of it's live rock concenrated in an 'island at one end of the tank, there are two vertical pillars/masses getting to it. At the end with out much rock sits a big tunze powerhead pushing 6000 lph on a timer to provide 6000lph for about 8 seconds, and 2000 -3000lph (depending on how I set it) for 4 secnds inbetween. This effectively pushes waves along the tank that bounce of the front glass and wash over the rock mound. The larger rock pilar is designedto just catch the egge of the flow of water, and uses to turbulen flow to pull a mass of water round and behind it.
To collect debris settling behind the major mass of rock I have a Fluval 4plus with a 3plus body on it I tihnk.
That's it. In your example I would use a closed loop as you already have the pump, and powerheads are a real faff - the ones available in the US all seem to be horribly unreliable,( plus they inevitably have a livestock 'incidnet' mashed anemonae....), and getting them out to clean them can be pain. Plus lots of wires hanging around is a p.i.t.b.
It's good to try to understand what all this means in practicality. Water movement is probably the most vital thing to get right in a tank as it affects your filtration so much. I start with the rule simple is best, and think it's not a bad idea to plan for oversizing this stuff.
Photo of tank would be nice plus other info.