How to define Water Flow in L Tanks

[bigbird]

Hello All,

As you are aware in this wonderful world of Ls, some like fast water and some slow running water. I ask myself how do you define fast flowing water and slow running water in the tank ? I would just like to know if there is a measure or standard verifying the two.
IE I have a 5ft tank(L333/LG6 and L080)- Newly set up, I have one Eheim2028 filter, the outlet located on the back left with an aerator going to the back, then I also have an Eheim 2215 left sude spray bar going down and then on the left a powerhead 3000l/h. This then gives me circulation all around from back left to right then front right to back left so in a circle. Now I can see that this in my view would be fast water or is it still not enough movement ?
Then I have a 3ft (L134) with just one spray bar in the middle from Eheim 2213 and an airstone. Is this then slow water or is it not enough ?

Any ideas ? cheers jk :thumbup:

 

[Lornek8]

Anything we put on the tank will be slow when compared to their natural environment, evne for the "slow" water fish. Its all relative. There's no real way to define what is slow or fast.

 

[mike0605]

This is interesting and takes me back to something I read with diagrams when I first started to look at keeping L number plecs.

It is a bit of a messy looking setup but produces great water movement and I was considering adapting this method for some of the plecs from more fast flowing parts of the amazon to produce more of an undercurrent.

Basically the diagram I saw showed tubing being used in the aquarium connected at one end to a powerhead and the tube going down the inside side edge of the tank along the bottom and opening up a couple of inches above the bottom on the opposite side of the tank in principle this has all the benefits in terms of watermovement as an external filter but without the filtration i.e. purely water movement.

What I was thinking (don't know how good it would work) or if it has ever been used or tested was to have a tube going up the inside edge of the aquarium and opening up a few inches below the water surface where this tube hits the bottom of the tank have it go along the bottom to the opposite edge of the aquarium and go up that side say 4 or 5 inches so not right near the substrate then attach a powerhead. This would then pull water from near the surface which has effectively come from the bottom through the external filter, been filtered and returned to the tank, this filtered water would or some of it would be pulled down the tube down across and up the opposite side of the tank then be released by powerhead which should basically create an undercurrent and mean that the water is moving alot around the tank when combined with the external filter (only negative I can think of with this is how messy the pipework leading to the powerhead would look and obviously this would most likely only benefit the plecs who really like the faster flowing water.

Thanks

 

[Lornek8]

I'm pretty sure i've seen the river tank type setup you're talking about.

What i'd like to see is a cylindrical doughnut tank so one could setup unidirectional high velocity current. I've seen similar tanks on a large scale for seawater fish but would be interested in seeing a smaller version for plecs. One of the problems with conventional rectangular tanks is that once flows get really high, you get all sorts of problems with rebound & swirling eddies.

 

[Stan]

Mike's post got me thinking that I'd seen an article like that somewhere too. After a morning of looking around I found it.:thumbup:
Designed with loaches in mind but just as useful for plecs.
http://www.loaches.com/articles/river-tank-manifold-design

 

[mike0605]

That's the one I seen a long time ago Stan.

 

[bigbird]

hi Lornek,

as you stated.. you get problems with rebound and swirling edges.....may I ask you what kind of problems ? I have set up my 5ft tank with back right hand powerhead and then also front left a power head, so get a circle motion of the water. Would I be better off just have the one direction ? cheers jk :thumbup:

 

[Lornek8]

As hard as we try it tough to mimic natural flow conditions in an aquarium. Maybe its just a problem for me, but even a circular flow in a 5foot tank isn't something a fish would typically experience in the wild. Its simply the limitations of a rectangular tank with flat walls. Don't get me wrong I'm not saying anyone is doing anything wrong. But if we're talking about trying to stuff a bunch of flow in a tank to mimic natural water conditions, typical setups don't do a very good job because of limitations. It works with wave makers & such in reef tanks as thats the type of flow you get in a reef environment but in rivers the flow is normally a bit more organized.

 

[bigbird]

thanks for your response. yup agree with that. I was even considering maybe a plastic childrens round pool, rocks in the middle and 3 powerheads even spread for a circular motion,, like you said in the earlier mail. anyway I have my rack now and am happy with my currents. will post pics soon. cheers jk :thumbup:

 

[dw1305]

Hi all,
I wrote some bits about water flow in "Aeration and dissolved oxygen in the aquarium" <http://plecoplanet.com/?page_id=829>, including pinching some bits from the excellent "Loaches online", mentioned earlier in the post, including this image.

One of the reasons for having fast flow is that it increases oxygenation, and high levels of DO are one of the major factors in keeping rheophilic fish healthy.

If you really want good water movement you really need to look at what reef keepers are doing:
<http://www.advancedaquarist.com/2006/6/aafeature2>
<http://www.advancedaquarist.com/2006/8/aafeature>
<http://www.advancedaquarist.com/2006/11/aafeature>
<http://www.advancedaquarist.com/2007/1/aafeature/>

If any-one has article 3, I'd be interested in it.

cheers Darrel

 

[bigbird]

thanks Darrel and all cheers jk :thumbup:

 

[AusPleco]

Did you end up taking pics bigbird?
I am having flow issues with my 4 foot at the moment where by i have an Aquaone CF1000 on one end with output aimed across the back of the tank then Aqua one aquis 1250 on the opposite side with outlet facing diagonally towards the front and bit to the right.

I still dont have much flow although i have modified my outlets with a bit of the filter hose so that they sit below the water line (fiancee dont like water noise and cant sleep).

I was thinking of adding my Aquaone 1000 internal liquid filter to assist but am unsure whether the benefits would be worthwhile. When i ran 2 canisters in my 3 ft it was great had good flow and i found my waste would all end up in a pile in the middle of the tank lol.

 

[bigbird]

will post over next few days. I have on one end an air diffuser attached to the outlet. picture soon to tell you more cheers jk :thumbup:

 

[Ike]

Sweet! Can't wait! I love looking at set ups.

 

[AusPleco]

bigbird lost the camera??

 

[bigbird]

:lol: give me a couple of days please cheers jk :whistle: