Sump design

[dickie]

I wasn't sure whether to post this in the DIY forum or the setup, so just chose here.

I'm considering plumbing a sump into an up-coming malawi tank. The tank itself is 48x18x18. Filtering without the sump would be done with an Eheim Ecco 2234 and an addition Eheim Ecco 2232. Adding a sump would obviously allow me to increase the overall volume of water used in the setup as well as adding to the filtration capacity.

The spare tank that I'd be using as the sump is 24L x 18H x 15D (I think, it's stored away at the moment so can't remember the exact measurements). This tank is already drilled in the upper left corner of the back of the tank.

The sump will be housed in a cupboard behind a the wall the display tank will be against.
I have 2 possible setups that I'd like some comments on....

http://dickieb.bulldoghome.com/pages/dickieb%5Fbulldoghome%5Fcom/cichlid%20sump.jpg

In this method I would drill a hole in the main tank and will feed the sump by gravity. The water would be returned to the tank by one of the eheim filters. The first compartment will house filter floss to remove particulates from the water column. This design will mean that in the event of the return pump failing, there will be no flooding as the water level in the tank will stop rising and therefore stop feeding the sump.



http://dickieb.bulldoghome.com/pages/dickieb%5Fbulldoghome%5Fcom/cichlid%20sump2.jpg

This method is sort of a reverse of the first one. Having the sump fed by one of the filters and returned to the main tank via gravity. This method means I do not need to drill the main tank and have an increased flow rate due to virtually no head height for the sump transferring water from the tank to the sump. I also believe that there will be increased biological filtration as I will effectively have an extra compartment for biological filtration in the sump.....this will also however mean that the capacity for removing particulates will be reduced.



The potted plants are optional....I just thought that it might be a way of helping with nitrates.

[MatsP]

A sump is a great way to filter - it gives a much bigger filter volume...

Unless you're desperate to not spend any money, I would recommend using a simpler Eheim pump to move the water around.

I've got two of the Eheim Compact pumps, 1000 lph model here.
. They don't produce a whole lot of head, but are OK for "low-lift" applications. When I bought my second one a few weeks ago, I think I paid £22. [One of these pumps is used to circulate the water in my water-storage in the fish-room, which is 2 x 25g "loft-tanks", which are connected by a 15mm connection [and a 15mm "full-bore" quarter turn ball-valve], and if I set the filter to "max" circulation, it overflows the recipient tank, because the 15mm pipe is too restrictive - admittdely, that's not a whole lot of head, the tank is about 650 mm tall - but it gushes out pretty quicklyeven when the tank is almost empty].

For more head, use the Universal pumps from Eheim. I haven't used these myself, but the LFS I do most of my business with have them in their sumps (including the display tanks that are custom made).

Caveat emptor: I haven't build a sump yet, so if it floods your house, don't blame me.

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Mats

[dickie]

I'd prefer not to spend any additional money. I may do that down the line to have a dedicated pump for the sump, but the setup of the tank is gonna cost enough as it is.

[MatsP]

That's fine. Just consider that you do need a height difference for the filter to work, external canister type filters don't actually work if you have them at the level of the tank, as they use gravity to take water in [although once you've got things going it works on suction, the pump won't be able to suck much "uphill", and you'll have great troubles getting the filter started] - I think you can do this, I'm just mentioning it so that you don't go "Oops" later on...

You should probably consider using some fairly course filter media in the filter that you use to pump water...

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Mats

[apistomaster]

MatsP is exactly right. Eheims have very little ability to work with head pressures. It is a misallocation of an otherwise perfectly well designed canster filter(s). It is far wiser to use Eheims the way they are designed to work at their peak efficiency. A separate pump that is specifically designed for the head pressure and desired volume of flow is the way to go. A very good high capacity pump that would pump ten times what the combined output of the Eheims used with head loss figured in can be had for less than $100US.

The concept of nitrogen export using plants looks better in diagram than it works in practice. You have to be able to remove a few pounds of wet vegetation regularly before you would be having any effect. The nitrates are produced faster than a reasonable volume of vegetation can sequester. Assuming recommended water changes are being made the nitrate levels will still fall within the standard deviation of enough tests whether you use plants or not.

[dickie]

A separate pump that is specifically designed for the head pressure and desired volume of flow is the way to go.

Yeah, I know that this would obviously increase the water turnover a huge amount, however, one of the points of this setup, is to keep as much equipment as I can out of the tank. Given the total surface area of filtration capable in the sump, I'm willing to lose a little waterflow.

If down the line I find that I want to use a pump, it will be an easy enough thing to incorporate. Fortunately, I have several kicking about that were made redundant when I broke my reef tank down.

Thanks for the feedback though

Dickie

[apistomaster]

FWIW, both Eheims can be used in the sump only. There are several advantages to that.
1. The Eheims will operate at full capacity.
2.They won't be intruding into the aquarium.
3.They will polish the water in the sump which has already been prefiltered twice,once as it goes through the overflow prefilter and again going into the wet/dry mechanical filter pad.
4. This tremendously extends the period between cleaning the Eheims.
5. Then the Eheims are operating as extremely efficient biological filters.
6. Because the sump water so clean you can reduce the amount of mechanical media in the Eheims and add even more biological filtration capacity to the Eheims than as when they are set up as a primary do all-filter. You would gain thousands of square feet of substrate sufrface area for the bacteria to colonize. That is nothing to sneeze at.
You would still need a primary pump to provide through tank and filters a disearable high flow rate.

I think you will just try your design and I understand that. I am more the doing ever more with ever less type, myself. KISS designs are proven best in commercial aquaculture and I raise and sell a lot of fish out of a very small operation. Other than my Heckel tank I don't keep any fish that do not provide a return on m investments.

[Graham Ash]

Hi Dickie
There is another low cost way of doing this filter

Simply take you tank filter and divide it up using sliconed pieces of perspex or glass so that you create a weir flow filter

All you need is basically an Eheim pump to then return the water back to the tank. The filter (underneath the main tank) is fed by gravity - the water simply runs through your filter - ie floss, then a media, out into the end and is then returned by the Eheim

You can of course use another system as a filter - use a pond filter instead - can be found really cheaply over here

I use Eheim 1060`s but am just going to trial out one of the new Eheim pumps which turns over 1,000 lph - you then have everything out of the tank, including the heater/stats -
Graham