Backyard Aquaponics
A place to discuss aquaponics

I don't mind if the water is coloured for a few days. I do like the idea of knocking the sharp edges off the scoria though

O yeah... thats right I used a presure washer and I couldn't figure out why there was still large chunks of sandy stuff. The pressure washer rounded them off but also made more particles

Does anyone on here know how much scoria costs? I was quoted $150 a ton but I have no idea how much volume a ton of scoria is. How many cubic meters would a ton of scoria be?

Follow up on my suggestion of mineral wool as a filter - I had hoped mineral wool might work but I did some checking and the binder could also contain formaldehyde and phenol depending on where and for what purpose it was produced. Better to stear clear of it's use in AP as jayendra pointed out.

Not sure how much exactly but I bought this:
1m2 scoria
1/4 m2 pebbles (7mm)

it was 97$ all up

P.S. Go to your local concrete supplier rather than a Garden Center as the prices are generally cheaper.

Do you mean the bit about the plumbing?

That's actually quite common. I'm not talking water gushing everywhere kind of leaks, but if you have a small leak in a screw thread or similar, once the bio-gunk forms, it can definately stop it. It's happened several times on my system, and others have seen the same result.

If you mean pouring milk into my system, forget it

Although we had a backyard swimming pool when I was young. It was connected to a sand filter and that managed to pull a large milkshake out of the water in only a few hours. It turns out one milkshake is way too much milk to have in your pool

i meant the milk.
Did the water not still go off? did the milk go off in the filter or did your parents flush it quickly?

I have no idea, my life was all about the swimming at the time

I currently have only two fish in my system, and they are being fed perhaps 1/2 a cup of feed per day. Even with only two fish, that's a lot of fish poop in the water each day, but the system deals with, and would deal with a lot, lot more, without any trouble.

I would guess the solids in a glass of milk would be less than a teaspoon full.

I've been trying to sort out something cheaper and lighter for my media. I was going to use 2/3 blue metal & 1/3 expanded clay. All expanded clay is just to damn expensive for me...but with only 2/3 rock its still too heavy.

My growbed which is 3m long x 1m wide x 0.5m deep works out to be about 1.5 tonne!!

I'm not skilled enough to make a stand that will hold that amount 1m off the ground and be stable.....without breaking the bank that is.

I hadn't thought of scoria so I will go off and check some prices for that.

Someone suggested to me using styrofoam balls....like beanbag pellets. I had a look into it and its used in garden mixes and doesn't seem like any nasty chemicals leech out of them.
So I was thinking maybe beanbag foam balls with some vermiculite mixed through and then about 200mm layer of expanded clay on top to keep it all from blowing away.

Anyone got any ideas about that?

I think vermiculite isn't so good because it works its way through you system and basically escapes, but if you find a good source of coke bottle lids, they might work.

The plastic washers inside some soft drink bottles are toxic, but coke and a few other soft drink companies now make lids without them.

I've been collecting some for a while, and plan on putting them through a garden mulcher to scuff them up a bit and give them more surface area by mangling them into random shapes.

I have no idea if they will work, but in South Oz at least, they remove the lids at recycling depots and have to pay to dump them, so they should come free.

I agree with Bullwinkle

If you are having trouble with the suspended clay/dust from scoria and your water not clearing up, just add some Gypsum to your system. The tiny particles of dust will never settle out of the water column due to their electric charge, adding gypsum changes this and allows the particles to bind with bigger stuff so it can settle out.
No amount of physical filtration will clear this up.

I found that no matter what you do, water runs clear before day three.

I suspect bio-slime cures everything.

It also fixes small leaks~.


bio-slime



~It doesn't fix a cracked head in your Verada*


*verified (anyone want to buy a Verada (runs fine in winter))

I know someone who's organic certification was delayed when they thought the gypsum they were amending their soil with was fine. It turns out the anti-caking agent they added to the gypsum was not okay.

For me scoria is much better than gravel, the hight surface/volume coefficient is very important, it condition the quantity of bacteria and thereby the efficiency of the growbed/biofilter. Furthermore the porous material allow the air to go in when the belt siphon is low and when the water goes up some tiny bubbles are kept under water and contribute a bit to the aerobic bacteria reactions