My River Tank Manifold

[Botia Robert]

Over the break I had the chance to build my first RTM.

I have built it for a 4' x 2' tank. I have 3 x Aqua Clear 70 (formally 802).

At the intake end I have modified the classical design and gone for 4 intakes. This is because I really want to keep the water supply up to the powerheads. My caution is because I intend on using this in a much longer tank eventually and I am not sure how things change over longer lengths.

My problem at the moment is sourcing the appropriate sponges! If anyone can suggest a specific product it will help me tell the LFS people what I need.

I have used the otto sponges for illustration only. I havnt made the intake pipes for the sponges yet as I dont know what size sponges I will use yet!

I hope the photos come through OK, and would love your feedback on this design.

[Graeme Robson]

Looking great!!!

Keep us updated BR!

[Diana]

I have seen similar sponges, but
a) Dark grey (Hides in the tank better)
b) Twice as tall (more surface and interior area to catch the debris)

The problem is I picked them up as part of a used tank set up ("Here is a bucket of stuff to go with that tank!") and I have no box to tell you what it is.
It also came with some green plastic fittings.

[shari2]

I'd worry about those sponges not providing enough bacterial colonization, as well as the fact that small pore sponges tend to get sucked tight to the intakes with a lot of flow and slow the flow badly. Stiffer, slightly larger pore sponges seem to work better...

[Botia Robert]

These sponges are too soft and too short and too narrow. I put them in the picture to show the layout at the intake end.

I cant find anything suitable in the shops here and this is way out of the square for the LFS to grasp.

I was hoping you guys could tell me what type of sponges you use so I can tell the LFS what type of sponge to order.

Would a DIY solution be OK. One guy said get some foam and cut it to suit. What do you recon?

[Diana]

Oh. OK.
I have used Aquaclear filter sponges for similar manifolds. They will still collapse if they are full of stuff.
The sponge that comes with the AC 50 is about right. I actually bought that larger AC110 (old number 500) and cut it into 8 pieces. Cut an X through one end of the sponge, and it will slip over 1/2" PVC fittings, filter intakes and similar sized pipe.
A variation is to use under gavel filter up tubes (thin plastic) and drill LOTS of holes. I used a 1/4" drill bit (about 6 mm). Cut this tube whatever length you want, and cut the sponge to fit. The problem is that these thin plastic tubes are not any standard PVC size, and I have had a hard time connecting the two. The next time I do this (make a drilled core for a sponge) I will use the thinnest PVC pipe, then I KNOW it will connect to the manifold!

[Emma Turner]

Hi Robert,

Have you looked in the outdoor pond sections for replacement media for pond filters? The sponges we currently have on our river tank manifold were replacement pond filter sponges. The ones I have are green in colour, quite large (~5" high) and quite coarse so they don't get clogged very quickly. You probably can get some with an internal core hollowed out (so it would slot straight onto the pipework) but my sponges were a solid cylindrical shape to start with so I just hollowed out a slit for the pipework using sharp scissors.

Emma

[Botia Robert]

Most of the articles on LOL mentioned using sponges from Pond filters. I will definately try asking for this but so far I havnt seen much pond equipment.
At the moment Diana's idea about using the sponge from an AquaClear500 HOB filter sounds good. I might get some similar foam and cut it to the shape I want.
The picture below is an Aqua Clear 500 sponge.

[Melgrj7]

http://www.thekrib.com/Filters/sponge.html
The first post on there is about making your own sponges.

[Diana]

I do something similar to the sponges that I make.
Is upholstery sponge good? I thought furniture material was treated to be fire retardant?

[Martin Thoene]

I don't know about fire retardants in upholstery foam Diana, but generally these foams are far too close-pored for this kind of use anyway. As stated in the link provided above most commercially available filter sponges for air-powered filters clog way too easily.

I've always recommended coarse pond pump pre-filter sponges because they don't block so readily. You do need to rinse them every so often, but I've only twice had a coarse type sponge like this implode on itself due to my NOT having cleaned them for ages. Mostly they can get a lot of crud in them without collapsing, even with big powerheads.

If one can bore a suitable hole in Aquaclear HOB filter sponges in order to fit onto the perforated intake tube in my design, then these are a readily available sponge that ought to work very well.

Martin.

[Botia Robert]

Finally I have found some suitable sponges for my RTM.

Most of the Aquarium shops here dont do much for ponds. After going to a sponge retailer I went to my last hope - the Hardware store (Bunnings). In their outdoor section with the water features they had some appropriate sponge.

I bought the smallest size but this seamed huge compared with what I have seen here. These sponges as you can see, are square section rather than the circular section I was hunting for. This makes them look even bigger and wider. I cut the height down from 200mm to 140mm. I considered cutting the edges off the square section but I will give it a go for now.

Due to the large width and cross sectional area I modifed my original design from 4 intakes back to the classical design of 3.

I would be interested in peoples opinions about the difference in sponge shape and size.

Here is the RTM minus the powerheads.

[Martin Thoene]

Those look excellent. I would be wary of attempting to cut off the corners because I doubt that you can do it symmetricaly, so it might look somewhat rough.
These sponges look like the big tall ones I bought from Swallow Aquatics in East Harling while I was over in England in 2006. I have one operating on the River-Tank manifold in my Clown tank along with a 4" high by 4" diameter round one. Still haven't used the other one.
Your's look like they might be the same and that grade of sponge is ideal for this use.

Martin.

[shari2]

They look like the one I have on my river tank. Same square bulky look. It works great, never clogs, rarely needs rinsing.

[jones57742]

Robert

IHMO and based on my experience you really did good with the manifolding on this one.


Robert and Folks:

This question is probably a knee jerk reaction to yall but I have never used a power head although I believe that the power head is sucking on the ports depicted at the bottom of the first photograph and on the left in the second photograph and the return flow is being discharged such that a river water flow is being created.
Is this correct?

The second questions are does the turbulence on the water's surface produce oxygen saturation in the tank water and if not what other equipment is necessary to cause oxygen saturation?

TR