Are red lava rocks stained, or are they naturally red?

[David Mitchell]

Quick question as I set up my first small system.

I am planning to use mostly hydroton for media, but also a 25% bottom layer of lava rocks.  The only type available at my hardware store are "red lava rocks".  Does anyone know if these are stained, and if so, is it a problem?  I rinsed them a lot, but still get red dust off of them.  The bag doesn't mention any stain or coloring as an additive. 

Second, if the system water gets cloudy (from whatever), is it ever reasonable to add a regular fish tank filter to clear out the residue, or does it resolve on its own?

[Robert J]

David,  Until I found my source for shale, I was heading down the same road you are on...  all that I poled said the same thing... Not a problem, but wash, wash, and wash again until the water comes out clear.  They are very dirty with red clay.

They have a farily nice surface area for bacteria growth and are generally cheap and light.  Those that I do have in my system don't seem to cause any problems--but I like expanded shale a lot better.  If I were to do my beds all over again, those that are horizontal would have shale in the bottom 2/3 and top 1/3 would be hydroton.  Shale is a lot easier on the fingers than lava rock, but hell on your fingernails.  If you want to consider shale, I can give you an email address for the seller...  He's happy to tell you if there's someone close to you with his product.  He does provide a lot of shale to universities.

[David Mitchell]

Thank you. I would be glad to contact your shale seller by email. And I will keep rinsing my lava rocks.

[Robert J]

[e-mail]

 

Problem with media is shippping.  Unless you're buying a whole pallet, cost can be enormous.  I managed to get a pickup truck load from WVU for $200.

David Mitchell said:

Thank you. I would be glad to contact your shale seller by email. And I will keep rinsing my lava rocks.

[Layne allen]

I am using a couple of cubic feet of red lava rock with no staining. The key was a through washing. I went with this option because of price and weight. Good luck