Sump Design Advice

[jjohnwm]

The only way that one medium is better than the next is if it provides more surface area per unit volume. That comment about 5 square feet per pound of biomass is...strange. If you have a sump...almost any sump, but especially one as big as you plan...you have enough room for biofiltration that even the cheapest stuff will provide enough surface area for enough bacteria to do the job. And beyond that...well, it can't get better and you won't get more bacteria.

Maybe one of the expensive designer media might...might...have an advantage if you have only a tiny biofiltration compartment and need to get the most of that volume. That isn't the case most of the time; it absolutely isn't the case here.

I chuckle when I read how K1, when used in a fluid bed, cleans itself by knocking off the older, weaker bacteria and leaving only the healthiest bacteria still on the medium. Who the hell thinks that stuff up? Even if they can "prove" this in some fashion, it is in a practical sense ridiculous and meaningless. The beauty of a sump is that you have vast amounts of real estate waiting for bacteria to colonize, more than ever will be needed for almost any bioload you care to maintain. I have some K1 swirling and dancing in one sump; my granddaughters like to watch it, and I got it for free, so that's the only reason it's there.

My other sumps, full of static media, are colonized by a bunch of flabby, out-of-shape, couch-potato variety bacteria. Despite the embarrassment this causes me, I know that they still manage to gobble up the ammonia my fish produce. What more can I ask? What more do I need? I can remove half of the media whenever I wish, to start a new tank, and the old filter will be back to full capacity within a day or so. Those lazy overweight bacteria still reproduce just as fast as the more athletic ones, and they eat just as much ammonia. Enough...is good enough!

 

[wesb2013]

To me, the most important part of a sump, is the planted refugium.
So in my 125 gal 6 ft sump, about 5 ft is dedicated to the planted section, and
about 1 ft is dedicated to biomedia, mechanical media and the pump.
I also find baffles to be a waste of time and effort.
The only semblance of a baffle for me is a Porret foam wall that acts as a barrier between the planted side and the pump/media side.
So that entire wall acts as mechanical media.
Photos below, of the Porret wall, were taken when it was set up about 3 years ago
View attachment 1538625View attachment 1538624View attachment 1538623
The amount of biomedia is also compact, the 3 little bags above, and a porous lava rock block, west of the Porret Foam wall are the only biomedia, and consume all the ammonia and nitrite coming from the 180ngal tank it filters.
Below are the water parameters this sump combination produces.
View attachment 1538626 View attachment 1538627 View attachment 1538628
The idea that one needs a large area for, and loads of bio-media is a bit exaggerated.
The biofilm area populated by ammonia, and nitrite consumers is determined by the ammonia and nitrite fish produce, not by volume of the media in it, or the medias surface space.
As you can see above the lack of ammonia and nitrite results show, the ammount of media used , and the plants in the refugium area take care of that.
View attachment 1538630View attachment 1538629
The aquatic, and semi aquatic plants, in the 5 ft refugium take on that task with a vengeance, another test result below.
View attachment 1538631
This sump/refugium has been set up in this fashion for at least 3 years.
I also use some terrestrial plants in the main tank, and sump.
View attachment 1538632
And here is the average population of the tank it filters
View attachment 1538633
The brown tint is from tannins I allow to seep in from surrounding vegetation.

Do you supplement your refugium with a CO2 canister? I haven't done any research on that part yet, but it sounds like it's a must-do.

 

[wesb2013]

Your comment about leaving randomly for two week periods is interesting as sumps typically need to have their rate of flow adjusted every few days as evaporation adjusts water level in the sump (but not the tank).

In my experience K1 as static media is ineffective. In my experience K1 as fluidized media is also suboptimal. I'm sure it must be xlnt in a specific application but I've never found it.

What will you have in the tank that might produce such a huge volume of NH3-4? Unless there's a heavy predator load or something else that's pretty unusual your bacteria media requirement will likely be much smaller than shown. Like, a single sock full of ceramic media in the water flow or similar.

duanes is the filter and water chem guru here. If he says anything that contradicts my view; take his.

This was one of my questions that I didn't ask. Thank you! Have you bothered using an ATO before? I won't use one at first, but may try one out down the road once everything is up and running real stable.

 

[duanes]

Do you supplement your refugium with a CO2 canister? I haven't done any research on that part yet, but it sounds like it's a must-do.

I do not supplement with CO2.
The only fertilization, is done by fish waste.
And as you can see, the plants are doing quite well.


Mangrove trees above
Water lilies below

Vallisneria below

 

[Trouser Bark]

This was one of my questions that I didn't ask. Thank you! Have you bothered using an ATO before? I won't use one at first, but may try one out down the road once everything is up and running real stable.

Never seriously considered trying one.

 

[duanes]

One other thing I don't do, is adjust the flow every few days.
Once I get a flow rate that works for my fish stock, and plumbing configuration, I set it, and forget it.
and don't alter flow during feeding.
Any bits that overflow into the sump, are eaten by the shrimp, or other animals in the sump/refugium.
Below is the normal flow used from sump to entering the tank,.
The pump is rated at 1500 GPH.

Water enters onto the west end of the main tank, traveling east along the its length to simulate a riverine, laminar flow, toward two 1" drilled overflows (to the sump) on the east end leading to the sump.

Below the average amount of turbulence/agitation of water from sump, entering the tank.

 

[duanes]

Here is one of the 1" effluent pipes to the sump (there are 2).
This is the one, on the east ens

I like to have them create as much surface agitation as possible, creating gas gas exchange.

There is another 1" effluent pipe about half way down, to the west.
I also use the sump as a grow out tank for cichlids too small to be added to the main tank.

Above a little Darienheros caught the other day, in the Mamoni River.

 

[wesb2013]

Ok, so here is what I have now.
- I enlarged the refugium to help me combat nitrates better
- I removed the baffle form the 2nd tank, and replaced with poret foam instead. (thanks for the tip duanes )
- I kept the 2nd tank alone. I like this setup as it give me flexibility for the future in case i want to add equipment or enlarge the refugium.
- I eliminated the intake chamber, and instead have the drains entering directly on top of my mechanical media, to free up dead space and also make the plumbing a little easier
- I decided to use a really large piece of foam as sort of a mechanical filter between the refugium and the pvc connector to the 2nd tank. I also lowered the pvc to the bottom of the tank instead of up towards the top to help reduce the chance of the return pump going dry.

Question: Will letting my drain lines come in directly on top of my mechanical filtration cause any problems with backup, or reduce the effectiveness of the mechanical filtration?