ok to uselava rock instead of hydroton in ebb/flow?

[darippa]

so I need some new medium and shipping hydroton costs me some $$ and I can get lava rock pretty cheap. Anyone use lava rock instead as a medium? Would mixing it with hydroton be better than straight lava rock? any issues to be aware of?

 

[peps1]

loads of people use lava rock in ebb and flow, IMHO Hydroton is better as it is proses to have no sharp edges and hence better for roots

 

[darippa]

thanks for the quick reply. That was the info I was looking for. I'll end up mixing the remaining hydroton with lava rock and using that.

 

[Haps]

I use mixed, makes a good aggregate.
H

 

[bbing]

my roots loved sending frillies into the nooks and crannies. Harder to clean. There are some boitic advantages with lava also. Stay away from the black stuff becuase ihas too much (iron??) something or another.

 

[NEARTHEBEACHBOY]

good to hear that cus i just bought a bag 20 mins ago.

 

[darippa]

Thanks for the info about the extra iron. it's back to home depot. Time to return the black ones and get the red ones.

 

[Sloppy Seconds]

The nice thing about lava rock is it is much cheaper than hydroton so you can toss it into your landscaping after your done and buy some new. I think your supposed to soak it in some peroxide overnight and rinse good before use. good luck.

 

[Don Cotyle]

I've been useing lavarock for years, the redish-brown is just fine. I rinse the heck out of it just because it has a fair amount of fine particals in the bag, never had to use peroxide to clean it but it couldn't hurt.

After useing it I find it also works great as a bottom layer in houseplant pots instead of gravel!

 

[darippa]

well I did a little test. Filled two 20oz bottles with tap water and added 1" of black lava rock to one of them. Ran a test for ph, conductivity, and iron content with a spectrometer. Here's the results. Plain water: ph-7.6, cond-17.06, iron-.01....rock water: ph-7.6, cond-17.07, iron-.07. It shows that the iron levels did increase very slightly. If you are using 8-6" square pots and a 25 gal reservoir and regular changeouts I think the increase would not really affect the plants negatively. I'll give it a try and see what happens. Hope that helps someone else. If I'm wrong please let me know.

 

[medical_shed]

Is lava rock able to maintain a microbial colony in normal hydro the same way it does in bio-buckets if you were to use organic nutes? That would be pretty cool.

 

[bbing]

it's what puts the "bio" in the term biobuckets. Or so I thought......

Ripper - thanx for the battery of tests. I tend to agree with you re: neg impacts, i'm pretty sure i see more def's with iron than toxicity from too much.
All I know is when I see the shit that grows in the black stuff in Pacific Islands, i start thinking it may not be such a bad thing for acid loving plants...

peace