MyAquaponics Tool
Biofilter Media Calculator
Enter how much you feed your fish each day and pick your media. We'll size the biofilter for you — based on the surface area your beneficial bacteria need to keep ammonia in check.
Tip: you can never really have too much bio media. Adding 10–20% above the figure above gives your colony room to handle feeding spikes and warmer water.
How the calculator works
Biological filtration is a numbers game: every gram of feed adds waste, and your bacteria need enough surface to live on to process it. Here's the logic behind the result.
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STEP 01
Feed drives waste
Uneaten food and fish waste both break down into toxic ammonia. More daily feed means more ammonia to convert.
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STEP 02
Bacteria need surface
Beneficial bacteria live on the media's surface. We allow roughly 0.03 m² of surface area per gram of daily feed.
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STEP 03
Surface becomes volume
Each media type packs a different surface area per litre (its SSA). We divide the surface you need by that figure to get litres.
Compare the media
SSA (Specific Surface Area) is how much bacterial "living space" a media provides per cubic metre. Higher SSA = more filtration per litre — useful when tank space is tight.
| Media | SSA (m²/m³) | Best for |
|---|---|---|
| LECA | 250 | Budget-friendly, static filters & grow beds |
| Bioballs | 500 | All-round static or moving-bed use |
| K1 Micro | 950 | Moving-bed filters where space is limited |
| Bio Media Filter Discs | 1200 | Maximum filtration in the smallest footprint |
Getting the best from your biofilter
What if I don't know my exact daily feed?
A common guide is feeding 1–2% of your fish's total body weight per day. Estimate the combined weight of your fish, take 1.5% of it in grams, and use that as your daily feed figure. When unsure, round up — extra media never hurts.
Can I mix different media types?
Yes. Many pond keepers run a static media like LECA or Bioballs alongside a moving bed of K1. If you mix, calculate each media's share separately and add the volumes together.
Is more media ever a bad thing?
Practically, no — extra biological surface only adds resilience. The limits are your chamber size, water flow, and budget. For moving-bed media, remember the 40–60% fill rule so it can still tumble.
How often do I clean bio media?
Rarely, and gently. Bio media isn't meant to be scrubbed — that kills the bacteria you've grown. If it clogs, rinse lightly in pond water (never tap water, which is chlorinated) and only a portion at a time.