Over the coming weeks we're developing a mini-series on our YouTube channel featuring a range of different Koi-related products from the Evolution Aqua range that we stock. First up is the Nexus filter, the specific model that Brad demonstrates in our video is the Nexus 220+ model.
Two sizes available
The Nexus comes in two sizes, the Nexus 220+ and the Nexus 320+. The first is suitable for Koi ponds up to 18,000 litres, and the 320+ is suitable for Koi ponds up to 34,000 litres. These are a great system, they run off the old school vortex idea, however, with a lot of things added to make them significantly more efficient.
How the Nexus works
Your water comes in via your inlet, coming into the inner chamber, spinning around in a vortex effect that allows your heavier solids to sink to the bottom straight away, which makes them very, very easy to flush out when it comes to cleaning time. As the water lifts up through the filter, it percolates through the K1 Media which is also produced by Evolution Aqua, and is a very good polishing media when it's in a static bed, exactly how we demonstrate it in our recent YouTube video, and how we use it in-store. Your water travels through the K1 Media and comes up and overflows via a three-inch pipe in the middle. That then leads on to the outer section of the filter, which is the moving bed, or fluidized bed as some people call it.
It works off the same concept with the media, however, it's in a different scenario. In a moving bed scenario it's got pressurised air pumped into the chamber and all around, allowing the media to be very agitated. This exposes the media to a lot of air and oxygen, which allows the aerobic bacteria which are trying to culture to thrive, which leads to good water quality, and helps the nitrogen cycle to start in your pond, which is the key to good water quality in your pond.
These filters are very good for helping the nitrogen cycle in your pond and they come with a good amount of media already, however, you can usually add up to double, or even slightly over double the amount of media that comes with them. If you're in a scenario where you're very, very stocked up with fish,
Either pump or gravity fed
You can run the Evolution Aqua Nexus filters in either a gravity-fed manner or pump-fed manner. Pump-fed is obviously where you've got your pump in your pond, pumping out to this Nexus on the side, which you would want to sit above your pond, the filter would fill up and then very simply overflow from the outlet, back to the pond. In a gravity-fed setup, you have a bottom drain four-inch or three-inch pipe running into the inlet of the filter. And rather than the concept of overflowing, you didn't have an external pump up placed after the filter, which would draw the water through the filter and allow gravity to replenish the filter that will space in the filter. Essentially, they worked very, very well in both scenarios. However, the gravity-fed scenario is what they're most adapted for and how they work the most efficiently in my opinion.
The bottom line
Nexus 220+ and 320+ are excellent filters, they are efficient and very popular as the Evolution Aqua range always has been. These make for a great idea when it comes to doing a big pond. There are a lot of other filters out there that are very, very good but also very, very costly. These hit a nice quality mark where they perform extremely well, however, they're also at an excellent price point and are very reasonable to buy, which is why they're such a popular filter and why we recommend them to our customers.
Get in touch for more details
For more details about the Nexus range of filters from Evolution Aqua, or for any other specialist aquatics advice you need, get in touch or visit us in-store and a member of our team will be happy to help.