Can I mature a new filter quickly?


Luckily, yes! The simplest way is to add things from a mature aquarium - as Neale Monks explains...

Q) When it comes to filter maturation in a new set-up, are there ways to speed up fishless methods such as using ammonia?


A) NEALE SAYS: Luckily, yes! The simplest way is to add things from a mature aquarium. Bunches of live plants are a good start, especially floating plants, which have all the useful bacteria on their feathery roots, ready to seed the filter. Floating plants will also remove nitrate from the water, often very quickly as they tend to grow rapidly under good lighting, independently of things like substrate type and CO2 fertilisation.

An old school approach was simply to add a few handfuls of gravel from an established tank to the new one, but bear in mind the bacteria we want are highly aerobic, and live on the very uppermost layer of gravel, down to maybe a centimetre or so. But by far the best way to seed a new filter is to add live media from an established filter. This is called ‘cloning’, because you can essentially divide the media in an established filter into two equal portions, put one portion in the new filter, and end up with two filters that work equally well.

Bacteria multiply very quickly, given the right conditions, so even if the mature filter loses half its biological media, the dip in performance will be very brief and probably undetectable. The only downside to cloning filters or adding plants and gravel from other tanks is that you’re also carrying across any pathogens in that tank as well. If the donor tank is one of yours, and you know the fish are healthy, then the risk is trivial. But if you’re taking plants or gravel from another, unknown tank, you might not feel quite so secure.