Aquaponics - A Filter Is Needed!

The water in the fish tank was getting polluted with more and more suspended solids and the fish were getting depressed. The suspended solids were mostly from the fish pooh and loose earth that came with the pebbles. I did not wash the pebbles because they seemed to be OK when I started moreover I guess it is impossible to wash them. From what I observed, the outer layer of the pebbles seemed to have melted with the constant contact with water and is causing the water to be murky. The discharged nozzles got clogged after a week with these suspended solids in a slimy clump and cleaning is done on a weekly basis. The sliminess is an indication that there are organism breaking down the waste into nutrients and I am pleased but not with the clogging.
The murky water, sad fish and clogged discharge nozzles is not a good sign. I decided to do something because I want to have tasty fish and "Happy fish are tasty fish", also not having to clean the nozzles that often. At first I thought of just a simple suspended solid trap like a sieve of some sorts and after some considerations I guess it would be a waste of good resources.


Bio Filter Schematic 

Maybe I can just build a bio-filter base on the same principle as what I did for my little water fountain. It had been running for almost 3 years with no maintenance at all and it is still functioning perfectly. OK I'll do that.

Checked the water pressure at the regulating valve purging side and the discharge water looks strong enough so no need for additional pump. Take stock of what is available to be recycled and reused. I had to spend $4.80 only for a short length of piping and some fittings.

I have quite a few of these pigment drums which I got them free quite a few years ago and I just had no use for them for the time being. It is just the right size and is perfect for the bio-filter vessel body. Made a hole to fit a return tube for filtered water into the fish tank.


Filter material 

The filter material is some sorts of synthetic wool which I extracted from an old couch waiting to be dismantled. The actual material used were scrubbies but I guess the synthetic wool will work just as well.


Foam 

In case of scrubbies you can weight them down with some pebbles but with this synthetic wool I'll have to make use of a foam to keep them down so that any loose fiber would not flow into the tank.


Shape for tight fit

I have some old foam seat cushion and it was just perfect for this purpose. I have to cut it slight larger than the circumference of the tub for a tight fit so that it can hold the wool down.


Installed

The bio-filter took me slightly more than an hour to make and it was being installed in the evening.


Happiness 

When I take a look early the next morning, the water was already crystal clear and guess who were smiling and going to be tasty again?

The Veggies? They are delicious ... Yum!!!