Perlite

[M Cosmo]

I have heard that some people don't recommend Perlite in an aquaponic system.  Is anyone else using it?  Do you know of any reason to not use it. Please let me know as I am now about 80% rock perlite in my system. 

[TCLynx]

Perlite is incredibly hard to contain. Since it floats it is even harder to deal with. It seems to love escaping and can clog drains and if it does make it's way to the tank where your pump is, it can get into a pump and could do damage. The really big agriculture stuff is a little better than the stuff they usually sell at the garden centers but it can also break up into smaller pieces and become more of a problem with clogging screens and such.

In normal flood and drain aquaponics I see no reason to ever bother with it, it is usually more trouble than it is worth. It is too light to provide much support to the plants and if being watered often, it tends to stay too wet.

The only real benefit I know with the perlite is that it is so light weight.

Now for you situation, light weight is really important in the vertigrow stacks so it might still be worth the trouble but do plan some easy to clean/swap screening to catch the stuff so it doesn't get back to your sump tank and such.

I had some left over from aquaponics years ago so I used it in a few situations. I'm still cursing the stuff as it surfaces when I move gravel or re-arrange grow beds.

When handling the perlite, it is important to keep misting the stuff since the dust from it is really bad for the lungs. handling new/dry perlite is almost a two person operation, one to operate the mister while the other scoops perlite.

[Earl ward]

Like TCLynx said perlite floats actually from my experience it sucks. I tried using it in vertigo pots with coco fiber; it did not work very well. The perlite would escape and clog lines. The coco would remain to wet. I want to reincorporate the vertigo pots again but not with perlite. Thinking about orchard bird netting or lava pebbles with a contstant flow both would be light enough

[TCLynx]

Small lava rock would probably be a pretty good choice (of course I've see some lava rock float too.) The bird netting might not be so easy when it comes time for planting/replanting but I've never tried something like that as media.

Earl ward said:

Like TCLynx said perlite floats actually from my experience it sucks. I tried using it in vertigo pots with coco fiber; it did not work very well. The perlite would escape and clog lines. The coco would remain to wet. I want to reincorporate the vertigo pots again but not with perlite. Thinking about orchard bird netting or lava pebbles with a contstant flow both would be light enough

[Earl ward]

I have used the bird netting to build bio filters for ponds I think it would work but your right it would be a pain. I have also thought about gutter guard. It’s made to fit a 5in house gutter cut in a triangular shape so when it fits in the gutter water goes through but the leaves and other debris stays on top and blows away. When you put two together you get square to small for the verti gro pots ,but I think it would go into a PVC fence post cover nicely

[Jesse Hull]

Be cautious of using lava rock. Get only the stuff sold specifically for pond/aquarium use, even though it's more expensive than the bulk stuff you can get at landscaping companies. Lava rock is often used for industrial filtration prior to being re-sold for decorative purposes, and can therefore contain dangerous heavy metals and other contaminants.
Sweet Water almost bought a large amount to use in our bio-filters! :( Luckily I was consulted just prior to making the purchase, & when the yard guys were asked about it, they all confirmed what the rock's prior history was.

TCLynx said:

Small lava rock would probably be a pretty good choice (of course I've see some lava rock float too.) The bird netting might not be so easy when it comes time for planting/replanting but I've never tried something like that as media.

Earl ward said:

Like TCLynx said perlite floats actually from my experience it sucks. I tried using it in vertigo pots with coco fiber; it did not work very well. The perlite would escape and clog lines. The coco would remain to wet. I want to reincorporate the vertigo pots again but not with perlite. Thinking about orchard bird netting or lava pebbles with a contstant flow both would be light enough

[Jesse Hull]

One thing I haven't seen mentioned here is that perlite is dangerous to fish. It breaks down easily into smaller and smaller particles and abrades the fish's gills after entering the water. You'd be hard pressed to screen these finer particles out.

Also, yes -perlite is indeed bad for our breathing as well. As a ceramic artist, I am constantly reminded of the condition termed "silicosis" that has either taken or impeded the lives of many potters. Fine dust can stay airborne for hours, long after you can no longer see it (as a matter of fact, it's the stuff you can't see that is the most dangerous). After entering the lungs, scar tissue grows over the particle and that portion of your lungs can no longer take in oxygen.
I'm currently using perlite to open up the structure of the coco/worm casting mix for tomatoes and peppers growing in buckets until the greenhouses we're building outside are finished. These plants will be grown hydro-organically using a fish water based fertilizer tea in a non-recirculating method. Once the systems are integrated with the fish tanks, perlite will not be used in the gardens at Sweet Water.

TCLynx said:

Perlite is incredibly hard to contain. Since it floats it is even harder to deal with. It seems to love escaping and can clog drains and if it does make it's way to the tank where your pump is, it can get into a pump and could do damage. The really big agriculture stuff is a little better than the stuff they usually sell at the garden centers but it can also break up into smaller pieces and become more of a problem with clogging screens and such.

In normal flood and drain aquaponics I see no reason to ever bother with it, it is usually more trouble than it is worth. It is too light to provide much support to the plants and if being watered often, it tends to stay too wet.

The only real benefit I know with the perlite is that it is so light weight.

Now for you situation, light weight is really important in the vertigrow stacks so it might still be worth the trouble but do plan some easy to clean/swap screening to catch the stuff so it doesn't get back to your sump tank and such.

I had some left over from aquaponics years ago so I used it in a few situations. I'm still cursing the stuff as it surfaces when I move gravel or re-arrange grow beds.

When handling the perlite, it is important to keep misting the stuff since the dust from it is really bad for the lungs. handling new/dry perlite is almost a two person operation, one to operate the mister while the other scoops perlite.

[M Cosmo]

Thanks for the great information on why Perlite is bad for fish and the system. I will changing out the perlite for some Coir chips and some expanded clay aggregate. I will be posting the information on the Vertigro media forum.