Backyard Aquaponics
A place to discuss aquaponics

pad it up with shade cloth at the outlet end. I used filter material, but thats gonna get chokkas too quick. if you use the screenings and pack it in tight and then dont disturb it it should catch all the shite

If ya dont use steves idea, i suggest a (diy) fluidbed sand filter. Its what i am going to use in my system. Literally anything can be bio media, but sand has by far the largest surface area to volume ratio, and hence the most room for the bacteria to colonise and do the nitrogen cycle tango..

Eg:
half inch river gravel 90 ft Surface area/cu ft
Japanese Mats 120 ft Surface area/cu ft
[highlight=red]Sand 156 sq meters per GRAM!!!!!!!![/highlight]

(sand has to be fluidised to be a bio media though)
Oh and the page has some "Fun" maths to work out how much ammonia can be converted by the bacteria....

http://wernersponds.com/biofiltermedia.htm

thanks daniel!

one thing i read about fluidised beds was that they don't take kindly to a power down, in that the bac crashes quite quickly due to almost instant loss of DO. dont know how true it was.

i can see the price of pot scrubbers going up!

i have heard the opposite, that they can recover pretty quickly from power outages, and can adjust to increased bio loads very quickly......

When i find out from personal exp i will let you know.....

Oh and there are a few plans on the internet, but my fave for simplicity, and cheapness (this is the one im gonna make..) Found this from perusing the forum, never found this one from googling......

http://www.angelfish.net/yabbse/index.p ... 45;start=0

Yeah, i havent been able to find them here though, have found basically the same with a "useless" plastic handle....im sure those plasticy ball shower scrubby things would be just as good though (plenty of them around)

keep us updated on the FB filter

I like the figures on surface area, Daniel. Good find. I wonder if we can get them to re-check lava rock. I would think that would be higher than river gravel.

Hmmm...I see their point about clogging the pores on lava rock, but also, it looks like in their picture, the lava rock is the size of a small boulder. smaller pieces would be better.

Yeah Janet, I was suprised by that too, but i guess in this case size really does matter

And fb filters are self cleaning, so theres not a build up of solids or gung that needs cleaning, but i would put it after a mechanical filter if one is going to be used, as i am sure the sand would break up the solids into much smaller pieces

Hey Daniel:

Check this out, don't know how well it would work but might be worth trying (see the drain diagram):

http://backyardaquaponics.com/forum/vie ... &start=135

If you put a larger diameter adapter on the top part of the filter it would slow down any sand that got that high and keep it from going out the drain.

Go to the "dollar store" to find nylon scrubbies.

Thanks Dave, i am gonna look through your system to see, but did you manage to fluidise the sand with air? i tried that once but nothing even resembling sucess so i gave up on it......

Nope, it's just a sketch. Good data...

OK thanks




Yeah i have looked there, no luck.....