A 16 to 38 litre aquarium holds very little water, so dissolved organics concentrate quickly. The yellow cast that takes a year to appear in a 200 litre tank can show up in a nano tank in a couple of months, and a single piece of new driftwood can tint the whole volume tea-brown within days.

Carbon is the only stage in this filter that does anything about that. It is worth being precise about what it will and will not fix.

Bioscape does not publish a fixed replacement interval for the Tropic hang-on media. The closest figure the manufacturer does publish is 4 to 6 weeks for activated carbon in its PRO canister range, and that is a sound guide here. Two cartridges is therefore roughly two to three months of continuous carbon use.

The Tropic "Easy Clean" range covers three sizes and the cartridges are cut to each body. The flow rate is printed on the filter.

Suitable for

• Bioscape Tropic Easy Clean 60 hang-on filters, 160 L/h, freshwater or marine
• Clearing tannins after adding driftwood, botanicals or leaf litter to a nano tank
• Stripping medication residue once a treatment course has finished

Not suitable for

• The 320 L/h or 450 L/h hang-on filters — use BIS531B or BIS532B
• Bioscape PRO canisters, Tropic canisters or Velocity internal filters
• Running in the filter during a course of medication — see the warning below
• Blackwater and botanical setups where the tannins are the point of the tank

• Take the carbon out before you medicate. Activated carbon adsorbs most aquarium medications, often stripping a full dose out of the water within hours. On a 20 to 30 litre tank that happens faster still. Remove the cartridge before dosing, and fit a fresh one afterwards to clear the residue.
• Rinse the cartridge before fitting. A few seconds under running water clears the carbon dust that would otherwise cloud a small tank on start-up.
• Do not leave an exhausted cartridge in place. Spent carbon adsorbs nothing and simply restricts flow through a compact hang-on chamber.

• Write the date on the cartridge. Carbon looks identical on day one and day ninety. There is no visual cue, so the calendar is the only reliable guide.
• Change one thing at a time. Swapping the carbon and rinsing the foam in the same session strips more biology than a small tank comfortably absorbs. Space the jobs a week or two apart.
• Carbon is optional. Plenty of nano keepers run this filter with foam and bio balls only, and fit carbon when there is a specific job for it. That is a perfectly normal way to run the tank.
• Never recharge it. Baking or rinsing spent aquarium carbon does not restore its capacity. Once the adsorption sites are occupied, they stay occupied.

• Bioscape 160L/h Hanging Filter Foam 6 Pack (BIS530A) — the mechanical stage ahead of the carbon. A clogged foam starves the whole filter.
• Bioscape 160L/h Hanging Filter Bio Balls (BIS530C) — the biological stage, and the one that actually keeps ammonia at zero.
• Bioscape Premium Carbon Pouches — loose pouched carbon for a short course in a second filter or a quarantine tank.
• Bioscape Tropic Easy Clean Hang-On Filter — the filter range this cartridge is cut for.

Bioscape warrants the Tropic Easy Clean hang-on filters for 1 year. Filter media is a consumable and is not covered by that term. Your rights under the Australian Consumer Law apply to this product and are not limited by any manufacturer's warranty. Ships as a standard parcel.

How many cartridges are in the BIS530B pack?

Two. BIS530B is supplied as a two-pack of activated carbon cartridges for the Bioscape Tropic Easy Clean 60 hang-on filter, so one pack covers roughly two to three months of continuous carbon use.

How often should the carbon cartridge be replaced?

Bioscape does not publish a fixed interval for the Tropic hang-on media. The manufacturer's own figure for activated carbon in its PRO canister range is every 4 to 6 weeks, and that is the sensible guide for this cartridge too. Carbon gives no visual sign of exhaustion, so replace it by the calendar rather than by how it looks.

Will activated carbon remove medication from my tank?

Yes, and that is the most common reason a treatment fails. Carbon adsorbs most aquarium medications, frequently within hours of dosing, and it works even faster in a small water volume. Take the cartridge out before starting a course, then fit a fresh one once the course is over.

Does carbon lower ammonia or nitrate in a nano tank?

No. Activated carbon has no meaningful effect on ammonia, nitrite or nitrate. Ammonia and nitrite are processed by the bacteria living on the bio balls and foam, and nitrate comes down through water changes or plant uptake.

Will BIS530B fit my 320 or 450 L/h Bioscape hang-on filter?

No. The 320 L/h Tropic Easy Clean 80 takes BIS531B and the 450 L/h Tropic Easy Clean 100 takes BIS532B. The three filters have different cartridge chambers, and the flow rate is printed on the filter body.

Do I have to run carbon all the time?

No. Many keepers fit carbon only when there is a job for it — clearing tannins from new wood, removing medication after a course, or lifting a yellow cast out of an established tank. Running the filter on foam and bio balls alone is a legitimate way to keep a planted or blackwater nano tank.