Some time ago I converted a chamber of my multi-bay filter to aerated K1 and used a perforated sheet to prevent the K1 being lost when flushing the filter or doing a water change.
[img]http://i33.photobucket.com/albums/d95/kayos ... er001a.jpg[/img]
Unfortunately, since then I've struggled to keep the bottom of the chamber clean as normal flushing proved inneffective. I've actually had a 3-4 inch build up of crud in about 5-6 weeks when I've not had time to remove the K1 and perforated sheet to clean it properly more often. If you've used a similar shhet to contain your K1, it's well worth the trouble to check under it!

This picture shows the amount of crud that was left after flushing the chamber for a full 30 seconds, just 4 days after the chamber had been drained and hoovered clean.

[img]http://i33.photobucket.com/albums/d95/kayos ... G_1425.jpg[/img]
A quick chat with a certain Mr Davis soon provided the answer - Thanks Mark!




[img]http://i33.photobucket.com/albums/d95/kayos ... G_1428.jpg[/img]
The solution to this problem was easier to find than I expected. A quick trip to the kitchen for a cuppa while my better half was doing some washing and there it was - a small mesh bag for placing the washing tablet/gel in - one free with every box so there had to be a spare

[img]http://i33.photobucket.com/albums/d95/kayos ... G_1429.jpg[/img]
Just add a cable tie, drill the air holes out from 2mm to 3mm to get larger bubbles (another Mark Davis tip), fix the air pipe and the job was finished.

[img]http://i33.photobucket.com/albums/d95/kayos ... G_1430.jpg[/img]
End result? - space for more K1 and much better movement.
An end to the crud problem? - I'm pretty confident, but will let you know!
Cheers