This kit contains 3kg of Biohome Ultimate, one set of coarse, medium and fine foams, a strip of coarse and medium foam plus lots of gel filter starter balls to seed the filter with beneficial bacteria and level out any ammonia or nitrite spikes as the media matures.
If the kit is used for a mature system it is best to swap out old media gradually (over a month or so) to make the transition as smooth as possible. Once the new media matures in the filter it should last 6-10 years at high efficiency and resetting the media is as simple as baking it in a hot oven for 45-60 minutes to remove organic matter and reopen pores.
Foams for outer parts of trays should be cut to 37.5cm (14.75") x 9cm (3.5") - one strip of coarse and medium is already cut in this kit. You will be able to cut 3 foams from each 17" x 11" coarse and medium foam so as this kit has 1 x coarse and 1 x medium full foams (11" x 17") that gives you enough for the trays of the Fluval FX4 filter.
The fine pads can be carefully ripped to a suitable thickness then cut to size for the top tray - you only need one fine pad on top of the top tray.
Full kit contents:
3kg Biohome Ultimate
1 x Coarse deep profile foams 11" x 17"
1 x Medium deep profile foams 11" x 17"
1 x Fine pad 11" x 17" x 1.25" thick
Strip of coarse and medium foam
Gel filter starter balls
An information sheet is also included which has useful notes about general filtration, filter set up, beneficial bacteria and chemical media usage.
This video shows the full set up process: https://www.youtube.com/watch?v=yrOqfXG2nL0
Please note: This is a compatible kit which is not sold by Fluval. It will upgrade every part of the filtration process.
Using the coarse and medium grade foams around the outer part of the trays ensures that any particles in the water are removed more efficiently compared to the standard filter set up. Anything remaining will be caught by the fine pad and the water will then be clean before it passes into the filter media (ensuring that it stays very effective at holding beneficial bacteria).
The Biohome Ultimate is extremely porous and has a huge accessible surface area for bacteria to colonize which makes it many times more effective compared to standard media (check feedback).
The gel balls will dissolve over weeks or months (depending on water quality) ensuring that the filter media is seeded very naturally to avoid a 'boom / bust' bacteria bloom in a new tank.