Media to Waste Ratio

[aarhud]

Hello,

Is there a formal calculation for the amount of bio media needed?

I'm designing a small acrylic box to function as an internal filter. I'm interested to know if there is some type of way to measure the ammonia/nitrate processing capacity of x amount of media. The tank is 18 gallons and will hold a dozen pencil fish are a pair of apistogramma.

I want to make the acrylic box large enough to hold the heater and function as a biological filter.

 

[gerald]

Pentair Aquatic Ecosystems has some good reference articles on their website, for aquaculture and hydroponics - might find some calculator tools there. Just guessing I'd say a quart of foam, gravel, or small lava rock should be more than enough. Aquarists typically err on the high side; you never know when something's gonna "upset" the filter bugs and you temporarily have less-than-optimal nitrification. And with enough plants to balance the animal load, you really dont need any nitrification.

 

[dw1305]

Hi all,

Is there a formal calculation for the amount of bio media needed? I'm designing a small acrylic box to function as an internal filter. I'm interested to know if there is some type of way to measure the ammonia/nitrate processing capacity of x amount of media. The tank is 18 gallons and will hold a dozen pencil fish are a pair of apistogramma. I want to make the acrylic box large enough to hold the heater and function as a biological filter.

I agree with Gerald, a relatively small amount of any media potentially contains enough sites for microbial action.

There isn't really a formula for the amount of media, mainly because it is the oxygen supply that really controls the level of nitrification. Scientists use BOD (Biochemical Oxygen Demand) as the metric for how polluted the water is. Successful nitrification just requires that the oxygen supply exceeds the oxygen demand, everything else is "froth".

I like to keep all the filter media aerobic, I'm not convinced that simultaneous nitrification/denitrification in a filter is ever a good idea. If you have a substrate and plants you shouldn't get a build up of NO3.

cheers Darrel

 

[gerald]

In modern municipal wastewater treatment, nitrifying bacteria are suspended in the water by aeration or mechanical mixers, along with the ground up solids and ammonia they feed on (use your imagination). They don't need any fixed bed of filter media like the older wastewater plants that used trickle-filters (usually small rocks). For aquarium use, fixed bed media makes more sense for keeping water clear enough to see the fish without a lot of suspended solids. And since 1 ammonium (NH4) --> 1 nitrate (NO3), if you have enough plants to consume all the nitrate (no build-up) then they'll probably uptake nearly all of the N-waste as ammonium, before it ever gets oxidized to nitrate.

 

[aarhud]

Thanks. I will certainly poke around Pentairs website. I did not know of their website, what a gold mine of info. I know the filter Companies push lots of bio-media and most of our fellow hobbyist seem to think the more the merrier. But the humble sponge filter can handle a fair amount of waste.

Reef tanks run off of live rock. I don't see why surfaces in a freshwater tank are any different as long as water flow is present?

For the DIY filter, picture a overflow box like what is on a drilled tank. I am playing around with a design to have water enter the top and fall down through the media before being pumped back into the tank. I think I can have a really clean look with black acrylic, while also being easy to maintain. Pulling from the top of the water column would keep oxygen content high.

I'll have to watch the water level in the fake overflow box. But other than that, I think it will work and look good. A lot cheaper than a canister.

 

[dw1305]

Hi all,

I know the filter Companies push lots of bio-media and most of our fellow hobbyist seem to think the more the merrier. But the humble sponge filter can handle a fair amount of waste.

Sponge is absolutely fine, and so are all the other biological media that companies sell.

Reef tanks run off of live rock. I don't see why surfaces in a freshwater tank are any different as long as water flow is present?

No they aren't. It is actually easier in a freshwater tank, because there are very few angiosperms that grew naturally in sea water. Plant roots are one of the factors that vastly increases the biological filtration potential of planted tanks, and marine macro-algae don't have roots.

For the DIY filter, picture a overflow box like what is on a drilled tank. I am playing around with a design to have water enter the top and fall down through the media before being pumped back into the tank. I think I can have a really clean look with black acrylic, while also being easy to maintain. Pulling from the top of the water column would keep oxygen content high.

Have you got room to pump the water up above the water level and then let it trickle down through through the media? I like the <"deBruyn type filters"> that run like this.

cheers Darrel

 

[aarhud]

Hey Darrel,

The DeBruyn filter would not work. The accent table is kind of in the open. So I am trying to hide as much equipment as possible.

I'm still tinkering with google sketch to find a design that would work for my purposes. I want to try something like this as an internal filter: (Minus the hole in the bottom of the tank)
http://www.nano-reef.com/totm/2015/january/tank.jpg

 

[gerald]

You can make an air-lift powered internal filter from pretty much any plastic or ceramic container, and hide it inside a log, branch pile, etc. There's no reason it needs to be fastened to the tank wall. I use Poret foam and small lava rock as media - they last forever.

 

[dw1305]

Hi all,

You can make an air-lift powered internal filter from pretty much any plastic or ceramic container, and hide it inside a log, branch pile, etc. There's no reason it needs to be fastened to the tank wall. I use Poret foam and small lava rock as media - they last forever.

An "Eck" Matten type <"corner filter"> would definitely be an easier option.

You could still put the heater behind the filter wall, and if you use black foam it merges into the back-ground.

If you don't have a huge fish load the foam should provide sufficient filtration, but if you wanted extra biological filtration capacity you could add Kaldnes type floating media behind the filter wall

cheers Darrel

 

[aarhud]

Air is out just because of noise. Unless there is a quiet pump. The tank is in our study room and the hum of the air pump would drive me crazy. If it was not for that, then I would defiantly go air powered on such a small tank.

I have a corner matten on my 125g tank and I love it. Hides equipment and looks nice! I was worried the corner would eat up too much room on a little tank. The kaldnes looks like what people refer to as K1? Would I need some kind of turbulence in the corner filter to move the kaldnes around?

 

[dw1305]

Hi all,

Air is out just because of noise. Unless there is a quiet pump. The tank is in our study room and the hum of the air pump would drive me crazy. If it was not for that, then I would defiantly go air powered on such a small tank.

I have a corner matten on my 125g tank and I love it. Hides equipment and looks nice! I was worried the corner would eat up too much room on a little tank. The kaldnes looks like what people refer to as K1? Would I need some kind of turbulence in the corner filter to move the kaldnes around?

You can use a pump/power-head rather than an air pump. I like "Maxi-Jet", they last for ever, an "MJ 400" would be fine.

The Kaldnes media is the "K1" type, I'd use the "K1 micro" size. It won't move around as much as it would in sump etc. but that doesn't really matter, if you have the sponge and plants it is only there for "belt and braces".

cheers Darrel

 

[aarhud]

I understand.

I found cell cast acrylic on Amazon for cheap and half of me just wants to have an excuse to play around with it. But The "box" is going to have to be pretty large to hold the heater and media. So it may end up being more unsightly than trying to hide the heater and small internal filter behind wood.

https://www.amazon.com/Acrylic-Shee...=1497285775&sr=8-1&keywords=cell+cast+acrylic

 

[gerald]

Craft stores and container stores have acrylic boxes of various sizes. Make this a far-south species tank (Bolivia, Paraguay, Argentina) and you can skip the heater.

 

[aarhud]

I have never thought of craft stores for containers. That would be cheaper and easier.

I could get by with far south during the summer. My house stays low 70s during the day and we turn the AC down to 68 at night. But we don't use much heat during the winter. I think the house stays around 60 degrees. We enjoy the cool weather while we have it!

I have never kept Hemichromis or Pelvicachromis (Other than some pulcher that did not make it past QT). I'm kicking around the idea of doing a westie tank. I have tons of anubias. I don't know how well Hemichromis would do in such a small tank. This does not scratch the Apisto itch either.....I miss the days where multiple aquariums were the norm lol.

 

[gerald]

P. pulcher or one of the small Hemichromis might work in 18 gal, but be ready to move them if it doesn't. I wouldn't try any of the other Pelv's in a tank less than 30" long. How about Anomalochromis thomasi?

 

[aarhud]

I had A. thomasi several years ago. I bought a group of 6 adults. They never spawned for me. MAYBE I had all males or females? From what I understand, there are two strains. The one Paul Loiselle wrote about was the form that is no longer available in the hobby. And the form that is in the hobby, does not breed as readily? I could be wrong.

Have you spawned A. thomasi?

 

[gerald]

Not me, but several others on this forum have - search the old threads.

 

[Mike Wise]

I've spawned 2 different forms, the Liberian H. thomasi (type form?) in the late 70s and H. sp. Guinea in the 90s. Both bred like flies for me. I couldn't give them away at the time (visualize chasing people down the hall at ACA conventions!). I understand there is still another population from Sierra Leon with red around the eyes. I don't know if it ever appeared commercially in the trade.

 

[Bart Hazes]

All my tanks have a generous layer of floating plants, up to 100% coverage, and that is in many cases the only filter. Tanks may or may not have a circulation pump. Even A. pantalone and Dicrossus filamentosus are happy in these setups and several wild-caught apistos are breeding. It also helps to cut down on the frequency of water changes as there is no build-up of nitrates. For a detailed description of the background, examples, and lab water test results you can read my blog http://biodives.com/blog/?p=6

 

[dw1305]

Hi all,

All my tanks have a generous layer of floating plants, up to 100% coverage, and that is in many cases the only filter. Tanks may or may not have a circulation pump. Even A. pantalone and Dicrossus filamentosus are happy in these setups and several wild-caught apistos are breeding. It also helps to cut down on the frequency of water changes as there is no build-up of nitrates. For a detailed description of the background, examples, and lab water test results you can read my blog http://biodives.com/blog/?p=6

Your blog is a good read.

Whatever reason most of the aquarium based literature vastly under-estimates the contribution of plant/microbe systems to biological filtration. If you have a look at the scientific literature there is a lot of research on phytofiltration, constructed wetlands etc. which offers a more balanced view.

Some of us use a similar philosophy, I've called it the <"Duckweed index">, although other floating plants are more suitable.

I also post along the same lines on few other forums, mainly <"UKAPS"> and <"PlanetCatfish">.

cheers Darrel