My Dumb Projects: A Bio-Filter Better Than Any Sold In Stores

Store-bought aquarium "bio filters" are mostly nonsense. This DIY ecological support scheme gives the beneficial aerobic bacteria air to breathe, immerses them in a constant flow of tank water, and provides vast space for their colony to quickly expand and recede as ammonia levels in the tank fluctuate, allowing better health, even for smaller, more constrained tanks. Simplicity of in-tank scheme removes leak/drip worries. Vertical surge leg prevents air-binding of pump.

Category:

Science & Technology

Tags:

• Bio
• filter
• biological
• filtration
• aerobic
• bacteria
• ammonia
• nitrate
• nitrite
• aquarium
• fish
• air
• pump

[waltmcmahon]

looks great, is it working like a wet/dry filter just using an airpocket under presure,or dose the air and water only have to rise up together not being presurized at all-making more oxygenated water in that area-i like using pot scrubers without the sponge

[consubandon]

@waltmcmahon The 1st one: Works like a W/D filter using an air pocket. Instead of dipping something porous in -and-out of the water, I'm just burbling air over the material. The point is not to "oxygenate" (tanks don't need oxygenation, anyway, as long as water stays moving via filters, pumps; there is no benefit from just blowing bubbles into a tank), the point is to provide a damp porous material with access to both water AND air.  Unless bio filter material is exposed to AIR, it does NOTHING.

[consubandon]

Different companies sell porous ceramic or plastic. Sometimes crumpled plastic strips or foam. If it has lots of exposed surface area, guess what? It's a BioBead! (Really! It's TOTAL B.S.) If I were making my own, I'd pull apart filter sponges and use the chunks. The device I describe will want to float so be sure to weight it down with rocks or something dense. (And, yes, the bacteria will live on the rocks, too.) You could put your grandmother's teeth in a glass and call it a bio filter.

[JennerPomo]

Hi I am a Native Amairican Indian and I do not mean to pop your bubles but my Basket weaving plants clean the water for my gold fish and all I need is a Airanater.

[marthale7]

I have been doing something similar with aquaponics. interesting idea. Thanks for sharing.

[espirates2]

All a bio-filter will ever do is remove ammonia and nitrites. Any store bought filter will do this effectively. HOB filters and Canisters do in fact provide oxygen for the beneficial bacteria. To say this is better than the store bought filters is B.S. 

[kokopelli314]

Sewage 101:

Anaerobic digestion-> without oxygen, requires heat, creates methane(removing nitrogen), slow, works best with continuous, higher concentration N and P

Aerobic Digestion-> uses oxygen, room temperature, creates CO2 and sulfur dioxide, faster, requires pulsed concentrations to allow endogenous respiration(the little bugs eat each other and themselves when times are lean)

Neither process removes phosphorus. It's only partially bound up in the bacteria. Plants are necessary.

[jaimejo77]

@gustopf I see what you're getting at now. Thanks for the reply!

[gustopf]

@jaimejo77

The bacteria most folks are concerned with are anerobic, meaning they need oxygen. Now they dont have to be directly in contact with air, Just well oxyginated water will work. As far as undergravel filters go, relying on the gravel not being to deep the water flow is enough to get oxygen down to the bacteria. But you also get pockets that lack oxygen and so aren't the most effecient.

[gustopf]

Interesting Idea, Not quite the way i would go but still worth the watch.

[jaimejo77]

If bio media "must" be exposed to air in order to work, then how do you explain undergravel filtration? No air exposure there...?

[cupcake1556]

Get a hair cut you Occupy Wall Streeter

[288CharlyBrown]

suggestion, pvc well pipe that is vented for the top and the bottom, place a air inlet in the bottom and make a connection for the water pump also in the bottom.. this will negate your air surge and allow flow.