Backyard Aquaponics
A place to discuss aquaponics

ROFL! Thats a damn good way that you've found there Red Beard

Wait, is it realy important to clean out the rocks? Won't it all just settle down into the system and be ok? Or does it harm the system in some way?

You need a fine but strong garden sieve, fine enough for the media not to fall through. The bigger the better. Set up on blocks or whatever at a slight angle. Then load the sieve to about two inches deep with gravel and working with a hose and a builders trowel rinse while agitating and moving the gravel up and down the sieve until the water runs clean. I had to wash 4 cubes of stone and this was the out and out winner for speed and ease from many different approaches. Uses lots of water though. Also get some of your fitter friends to come and help out with a promise of trout and a six pack of beer.

Yep, beer helps. And you can top up the fish tank now and then

But, afraid there's no other way around. No silt in the fish tank means washing gravel.
I've been washing gravel in my tractor bucket. What is left in the bottom after the gravel is gone is a very hard layer of silt. Imagine what that would do to your FT.

Half the idea of the media is that it acts as a biofilter, surface area for bacteria to grow on. If you don't clean your media then all of those fines collect in the bottom of your bed, clogging air/water spaces.

Then you have anaerobic spaces which aren't so great. There are some people who don't clean, but general consensus is that it's a good idea.

I dont wash gravel......yea I said it!

Got a trailer full of scoria and if I dont wash it, I reckon I would have a silt layer an inch deep in the growbeds and tanks
Its loaded with crap

Tractor bucket and a dip tin for me. Your arms are busy so your mind is free to dream up all manner of wonderous machines to make the job easier.

Maybe crank up the ol' cement mixer when ready to do mine...

Cement mixer will just mix all the fines and silt through the media.... cause that's what it is designed to do.

A cement mixer with water added of course will wash the gravel extremely well, but the gravel will need sieving before or after.
A purpose built trommel with water sprays would be the most effective way to wash gravel.

Cement mixer first then dump onto sieve and rinse with hose. Yes that would give you some nice clean gravel.

Have used mixer before to clean gravel, [not for aquaponics] use plenty of water and tilt the bowl to the point where larger pieces start to exit bowl and the fines gravitate to the bottom.
Havent tried this on scoria....so will let you know.

lava rock and mixer might just end up = dust or the wet equal

IBCs make this easy because there is a tap at the bottom. I just kept filling up the growbeds with water then pulling out the standpipe. The sudden water draining sucked out most of the fine dust, which flowed out the tap in the IBC FT. It took a few goes, but was easy on the back