Backyard Aquaponics
A place to discuss aquaponics

Coach,
Where did you find it and the ever important, how much?

Back to the original question...

I've got a growing mound of polystyrene cores form my rafts. Since the EPS does not have the fire retardant and based on the research done by the CSIRO that there are not any nasties I've been thinking of using them as a filter.

G concern about them breaking down may be warranted where they are allowed to move and exposed to the sun but since the foam is densest, which translates as toughest this shouldn't be an issue if they are not moving and not exposed to the sun?

Other materials you could use Chris since you have a landscaping business might be old poly pipe? HPDE or LDPE run through a chipper would give you an inert material for a filter.

Don't know if that is a good idea or not.

Can't tell you how much old poly pipe I'v e thrown away over the years. I'll bet your right about chipped pieces being a good filter media. I've seen shredded PVC also. The newer packing peanuts are soy based...but not sure how they hold up in water?? This is a link that I first looked at: http://myip.cctec.cornell.edu/index.cfm ... rom=search

If they are the ones I'm thinking of they just dissolve. Plus I wouldn't think packing foam beads would be a good idea because they would be heavily laced with human hormone analogues used as fire retardants.

I think PVC would be another good one but it wood be more prone to sharp edges.

Agreed, the PVC I saw was shredded pretty fine, it didn't look sharp. It's in the Pentair catalog Stu.

coachchris, the pellets you got have you a measurement on max min size?

2-3mm. they are polyethylene...I think. (it's early and before coffee) virgin plastic preinjection material. They look like grains of rice. They should work well, as long as I can keep them contained in my filter

Thanks for that, I didn't think they were that small.

What about vermiculite ...
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