How gULP operates as a mechanical filter
gULP can operate in several ways as a mechanical filter. As we know mechanical filters are there to trap solid particles that exist in Koi pond water in order to keep water visually clean. These solid particles should then be easily removed from the filter and discarded to waste.
Easy to say, much more difficult to get right in practise. gULP however has several tricks up it's mechanical filtration sleeve.
You can quickly configure gULP to run as a mechanical filter using:
plus probably a few other options we haven't thought about yet.
Note that gULP has a square sump located at the bottom of the filter. This allows you to be able to open a valve (everyday if you can) just for a few seconds to quickly and easily purge solid material that has settled out in the filter during the previous 24 hour period.
On the inside of gULP you can see the inner workings. The brush rack slots are clearly visible on the uppermost inner ring. These slots are exactly the right distance apart to ensure that when you hang brushes in gULP from a supporting pipe (you will have 4 of these racks in a gULP mechanical filter) the brushes overlap perfectly. Not too dense, and not too far apart either.
These brush slots also serve to keep the brushes firmly fixed in place. gULP accommodates 14 400mm brushes in total (two rack of three brushes and two of four brushes). This makes the brushes light enough to easily lift out and to hose down once a week.
Importantly brushes are mounted below water level and they have a large void space below them. This maximises the effective surface area used by the brushes.
2. Japanese matting
You will also notice that there are three such inner rings (the bottom one is right at the bottom of the filter). This is so that you can mount a stainless steel plate as a shelf directly inside the filter. Using such plates you can configure gULP with Japanese matting or sheets of sponge to act as your mechanical filter. These can be extremely effective as mechanical filters with a simple hosing down from above being sufficient to clean them.
3. Static Bed of SuperActiFlo
In this configuration gULP is setup in the same way as when we run gULP in a biological configuration using moving bed SuperActiFlo technology. The sole difference is that as a mechanical filter the SuperActiFlo bed is kept static (i.e. it is not agitated by air bubbles as it is in the biological moving bed stage), and it is only agitated when being 'backwashed'.
What happens in the Static Bed Filter is that solid particles in the water stream become trapped within the bed of media. Once a week aeration is injected into the bed, causing it to churn around and to shake these entrapped solid particles into the main water body. This water and solid particles are then simply flushed to waste via the sump at the bottom of gULP.