Backyard Aquaponics
A place to discuss aquaponics

Ok - so an online calculator I used tells me I need 1 tonne of Scoria for each grow bed. (1m X 1.2m and 45cm deep)

That seems very excessive! Especially at a cost of $200 per tonne from my local supplier.

So my question is - what is the best way to calculate how much scoria I need?

Thanks in advance!

scoria is measured in cubic metres, it is very light an a tonne would be more than your roughly one cubic metre.

find another supplier, i dont know what costs are like up there, but in vic it is around $65/m.

Your calcs would put you at needing about 1/2 cubic metre.

Thanks Yavimaya! At least your calculations have halved my costs.

The cheapest I can find it with an Internet search is $180 per cubic metre. The joys of living in Sydney!

I just called BCSands.

They're the cheapest so far and we deliver me 2.3 cubic meters for $530

ANL were quoting me 3 cubic meters for $640

Considering I only need 2 cubic meters I know who I'll be going with

Haha - spoke too soon. Turtle Nursery just quoted me $499.50 for 2.3 cubic meters of 14mL scoria

Make sure you test your media in vinegar. If you see a chemical reaction its not suitable for aquaponics.

Why use scoria when river gravel works very well, at a lot less cost?
1300kg/m^3, and $65/m^3 here

Getting better and better Martins Building a landscape supplies just quoted me $459 for 2.5 cubic meters incl delivery....

Because scoria is only 1000kg per cubic meter and given this is my first ever AP build I want something as light as possible without totally breaking the bank

Oh really!?! What does the vinegar test expose?

Limestone,shouldn't be a problem with scoria.,but it doesn't hurt to test.

So the calculator told you needed 2 m3 rather than the 2t you were originally talking about?

How big is your fish tank?

And Im guessing you have 4 GBs?

Scoria has far and away more surface area than gravel so wouldn't you get more bang for your buck from each growbed ?

I think its mined in Victoria so that's why its cheaper there. It doesn't contain limestone, so there's no need to test for it.

It helps if you have a groundsheet or tarpaulin for them to dump it on, just saves having to pick it out of the lawn. I've used 14mm and 20mm in different systems, others have used 10mm, I think the 14mm is a bit easier to work with than the 20mm.

Congratulations ! Your almost there !

I used scoria(red lava rock) in my grow beds. It had a lot of red dust with it and had to be rinsed before being placed in the grow beds. I would also suggest you keep a little extra, I had a few 5 gallon buckets set aside. After my system operated for awhile the media settled and I had to add a little more.