Flow In A Large Low Tech Tank

[NC10]

People say you should aim for 10x turnover but that is in part due to certain brands of filters only really supplying 50% of stated flow.

Regardless of what brand, actual flow rate, or expected flow rate, the 10x "rule" still comes into play.

It's up to individuals to test what their own flow rate is, after taking into account head height, how much media etc etc. I know not many people will actually do it, but it's pretty easy to put a jug under the outlet and time how long it takes to reach a litre, as you probably know from your tests. I'm guessing a lot of people will be shocked as well

I'm pretty sure though, that someone didn't come to the conclusion that 5x was the optimum flow and then said, just double it because companies lie by 50% how much is actually being turned over

 

[James O]

I believe 10x thing has nothing to do with filter capacity. It's purely a theoretical figure used to make sure there is more than adequate flow around the tank (allowing for media, head and pipework losses), ensuring plants receive maximum benefits from CO2 and probable EI dosing. Flow describes the delivery/movement of (possibly CO2/fert bearing) water around the tank.

I'm pretty sure for example, that Sanj and Alistair aren't getting 17,000lph and 14,000lph turnover via filtration[DOUBLEPOST=1404949768][/DOUBLEPOST]

..........for extra flow I just used wavemakers.

Sorry for derailing your thread, James. To take it back to the topic I'd recommend the Tunze Turbelle range for water-movement. Like your 2217s, they're energy efficient and no fuss.

Wavemakers (sorry been calling them powerheads ) seem to be the more practical solution as compared to a pump and spraybar. Btw no need for apologies, constructive conversation with practical experience is always valuable

So based on the fact that the up to 2000lph from the filters is not being taken as turnover rate, 2 or 3 wavemakers strategically positioned should be fine?

 

[Kev_M]

I'm pretty sure though, that someone didn't come to the conclusion that 5x was the optimum flow and then said, just double it because companies lie by 50% how much is actually being turned over

Actually, if you have a read about on here and other forums you'll find many posts from people saying exactly that. The other common one being to buy a filter that is rated for tanks twice the size of your own.

All of this is besides the point of course - which was two 2217s will be plenty on James' tank. Well, that and the fact he's asking for advice about flow (inside and around the tank).

 

[NC10]

Actually, if you have a read about on here and other forums you'll find many posts from people saying exactly that. The other common one being to buy a filter that is rated for tanks twice the size of your own.

I've never come across that but I'll keep my eye out for it now, see what they're saying. Do you have any links? I'd like to know how they were, or are, trying to deliver their 10x. Just to see if that plays a part.

It should go without saying really that you over do the filter slightly, you can always wind it back. If people are naive enough to not realise that manufacturers calculate straight from the pump without head or media, then so be it

All of this is besides the point of course - which was two 2217s will be plenty on James' tank.

It would as far as water filtering is concerned, but with additional tank flow via pumps and powerheads etc

I believe 10x thing has nothing to do with filter capacity. It's purely a theoretical figure used to make sure there is more than adequate flow around the tank (allowing for media, head and pipework losses), ensuring plants receive maximum benefits from CO2 and probable EI dosing. Flow describes the delivery/movement of (possibly CO2/fert bearing) water around the tank.

I'm pretty sure for example, that Sanj and Alistair aren't getting 17,000lph and 14,000lph turnover via filtration

 

[Edvet]

2 or 3 wavemakers strategically positioned should be fine

I use two koralia's (6000 and 12000) for extra flow in my large tank, paired with a 2-3000 liter eheim (wich just puts water through a sock) and app1500-2000 lit through the sump. I still was going to craft a diy spraybar to improve flow. Problem even in a large tank is the flowprofile of a circulation pump, to localized. In hindsight it would have probably been better to buy 10 small pumps and put them all in the back (like a spraybar), to get a wider softer flow. I pointed the big ones to the surface partially to soften the flow, i could lay the large plants "flat" easily had i wanted.

 

[sciencefiction]

On this 450 litre mbuna tank, I went through an FX6 (rated for 1500 litre tanks, but given your own criteria one of these wouldn't be fit to filter a 450 litre tank),

I am simply recommending what consistently works for me. I don't have problems with plants when I have lesser filtration and flow, neither do I have any water clarity problems in any planted tank. I have mostly problems with fish when my plants aren't growing up to expectations if the tank is averagely filtered and that's without ever detecting ammonia/nitrites on a test. Plants when not growing well produce waste and a lot of it.
It just seems with average filtration sometimes tanks can be unstable but one can be lucky. Plus any tiny ammonia rise triggers algae blooms even if it's in its non toxic form like NH4. So I try to avoid that by overfiltering which can be expensive if ones idea of filtration is Eheims.
So yes, in a 450l tank I'd have two FX6 rated 2130 each, maybe more But in a planted tank I'd probably opt for filters with spraybars that I can place along the entire length for circular flow.

 

[James O]

It just seems with average filtration sometimes tanks can be unstable but one can be lucky.

Or just maybe, perhaps there are some tank owners who are fully competent

So I try to avoid that by overfiltering which can be expensive if ones idea of filtration is Eheims.

So you've just called me and every other member that uses eheim filtration stupid without providing any credible evidence - thanks for that. What's your issue with eheim? It 'seems' to be clouding reasonable discussion, especially in light of this statement

So yes, in a 450l tank I'd have two FX6 rated 2130 each, maybe more

FX6 has equal filtration capacity to the 2217. The only difference is flow through the filter media. It simply cannot hold more filter bacteria than the eheim so it's only trick is more lph over/through the media. If speed of passage through media always equals better filtration then why do so many companies including eheim, fluval and ADA (to name a few) make comparatively low flow filters?

Baring in mind I was only talking about flow because I'm separating flow from filtration (I'm not taking filter flow into account at all) in a heavily planted low tech tank - spraybar or wavemakers for flow, Eheims for filtration with 4x turnover - why is an FX6 better?

 

[sciencefiction]

So you've just called me and every other member that uses eheim filtration stupid without providing any credible evidence - thanks for that. What's your issue with eheim? It 'seems' to be clouding reasonable discussion, especially in light of this statement

Sorry James but when did I call anyone stupid? I have an Eheim filter, it works fine. They just can be expensive to achieve the same thing in a large tank.
I don't understand why are you feeling offended by me expressing an opinion that two 2217s are not optimal filtration for the size of the tank in question?[DOUBLEPOST=1404997909][/DOUBLEPOST]

Eheims for filtration with 4x turnover - why is an FX6 better?

I really don't know. I haven't at all been comparing filter brands here. You are. I haven't used either FX5 or FX6 personally.[DOUBLEPOST=1404998086][/DOUBLEPOST]

Baring in mind I was only talking about flow because I'm separating flow from filtration

Well if that's your aim, then two All Pond Solutions 2000 EX will do a great job for fraction of the price

 

[sciencefiction]

Or just maybe, perhaps there are some tank owners who are fully competent

Maybe.
I apologize for my incompetent opinion. Please ignore my posts.

 

[James O]

And back to the original question, in my very first post, at the top of the first page...

Water flow is my present brain teaser. As this is low tech I don't need CO2 tank levels of flow but I know I still need movement to keep detritus moving to the filters and to transport ferts around the tank etc. I'm not planning to use the Eheims for flow, other than what a simple shepherds crook or similar can produce. This will give me longer filter cleaning intervals as flow won't be reliant on filter output which obviously drops with buildup.

My options as I see them are: pump attached to full length spraybar, or, powerheads (koralia etc)

What would you guys do?

Please no filtration discussion

 

[Tim Harrison]

The idea of a full length spray bar seems like an elegant solution - cost effective and good flow and distribution. Although, I suppose it depends on your final layout.

 

[James O]

I'm hoping for some form of floating plant like amazon frogbit or the mini pistia (water lettuce). These don't like to much surface movement if memory serves.

Would fish benefit from a variety of flow strengths? Some fairly fast areas and some quiet little corners maybe? Can you do this with a spraybar? Maybe the decor will break it up somewhat?

 

[Alastair]

I'm hoping for some form of floating plant like amazon frogbit or the mini pistia (water lettuce). These don't like to much surface movement if memory serves.

Would fish benefit from a variety of flow strengths? Some fairly fast areas and some quiet little corners maybe? Can you do this with a spraybar? Maybe the decor will break it up somewhat?

Given what you've stated in your initial post, filter outlets (one either end) I'd just add 2 newave 1600s, one under r each outlet and it'll give you more than ample flow all over the tank. When I wasn't running co2 on my 1400 litre I just ran 2 filters and two newave 1600s and this was more than adequate believe it or not. So I think roughly 6600 litres per hour or a bit less so around 4 times turnover.
Obviously now with co2 I'm running 2 BIG filters, 2 x Fluval sea 2800 lph pumps, one newave 1600, and a tmc 2200lph pump running the co2 reactor separately so around 9 times I'd say.

Sent from my D6503 using Tapatalk 2

 

[BigTom]

Yeah the Bucket was only at about 3x turnover but that was with a full length spraybar. I'd not worry about extreme levels of flow in low tech, just try and find a way of spreading it around the tank efficiently.

 

[dw1305]

Hi all,

Yeah the Bucket was only at about 3x turnover but that was with a full length spraybar. I'd not worry about extreme levels of flow in low tech, just try and find a way of spreading it around the tank efficiently.

I don't worry too much about flow either.

It is the much the same strategy that I use for lighting. I use whatever I have to hand, and then adjust the plants mass until it feels about right. I've got Eheim venturi in some tanks, and spray bars in others. I probably slightly prefer the venturi, but I'm not sure it really makes any difference.

I try and ensure that all of the filter media remains aerobic, so I don't really want any organic matter in the filter. I have a fairly large PPI10 sponge pre-filter on the intake, which I clean regularly.

I always have jungles with floating plants.

If I have fish with a high oxygen demand in a larger tank (bigger than ~60 litres) I try to have 2 filters on the tank (usually a pre-owned Eheim external together with an Eheim Aquaball or Maxijet power-head/sponge combination). You can see the Aquaball (and flow from the spray bar) in the picture.

There are more pictures in this thread:
<http://www.ukaps.org/forum/threads/water-lettuce-and-its-impact-on-my-tank.24109/#post-247162>.

cheers Darrel

 

[James O]

Thanks for the responses guys.

I think wavemakers will give me the flexibility I need. Do you think medium and low flow areas are possible to allow different planting and in tank climates for fish?

I picked up the filters today (thanks Kev) so all I need now is the tank.....

 

[dw1305]

Hi all,

Do you think medium and low flow areas are possible to allow different planting and in tank climates for fish?

Yes definitely, you can play around with planting and hardscape. Even in tanks that have fish with a high oxygen demand that like flow (Aspidoras, Hypancistrus etc), you can create areas where there is low flow. Even fish that like a current will spend times in areas with lower flow.

cheers Darrel

 

[James O]

Given what you've stated in your initial post, filter outlets (one either end)......

Sorry Just noticed this. The 2 inlets will be one end and the outlet pair at the other.

I figure one powerhead by the outlets, on the tank end facing along the length. Then another, halfway along the back facing diagonally toward the other tank end and the inlets. This should make for a more focused flow at the outlet end fading to a more gentle flow at the inlets.