hello all, I'm new here and new to pond building. I'm building a bio-filter and
need to fill it with lava rock. I went to the pond store today and they want
$40.00 a bag for small lava rock. Could I just use new BBQ grill lava rock? It
would be alot cheaper and isn't all lava rock the same?
-Pat Rolland

Go to Lowes or another home improvement store. lava rocks for landscaping
should be for sale there at about $6 a bag. I can go to the local gravel and
mulch yard and get a truck load for less than $40

Moon
remove nospam from e-mail to send to me, I grow trees in aquariums like bonsai.
I breed dwarf crayfish, great for planted community tanks. If you can get me a
shovelnose sturgeon fingerling (Scaphirhynchus platorynchus) no wild caught
please, contact me

Actually don't buy lava rock - too heavy, too hard to clean.
We use black vinyl screening. 50 yards for a 3,000 gallon pond. Clean once a
year - easy. Always smells river water sweet.


k30a

One thing great about TT is that the water get good oxygenation from flowing
down non submersed lava rocks. Do you suspend the screening horizontally as to
replace the lava rocks? Or are the screenings submersed? If the former, how many
layers do the water fall through before hitting the water level?

K30a wrote:

Actually don't buy lava rock - too heavy, too hard to clean.
We use black vinyl screening. 50 yards for a 3,000 gallon pond. Clean once a
year - easy. Always smells river water sweet.

k30a

and after that, use polyester batting. walmart. no fire proofing, no
anti-microbials. Ingrid

ESPMER (K30a) wrote:

Actually don't buy lava rock - too heavy, too hard to clean.
We use black vinyl screening. 50 yards for a 3,000 gallon pond. Clean once a
year - easy. Always smells river water sweet.


k30a

actually, all gravity type filters allow good oxygen into the media no matter what
the material is. Ingrid

Sean Dinh wrote:
One thing great about TT is that the water get good oxygenation from flowing
down non submersed lava rocks. Do you suspend the screening horizontally as to
replace the lava rocks? Or are the screenings submersed? If the former, how many
layers do the water fall through before hitting the water level?

K30a wrote:

Actually don't buy lava rock - too heavy, too hard to clean.
We use black vinyl screening. 50 yards for a 3,000 gallon pond. Clean once a
year - easy. Always smells river water sweet.

k30a

DH just layers the screening inbetween lighting
grid. Not sure how many layers, back and forth, in the 150 gallon stock tank.
It goes dead space and settling area, grid, screening, grid and then two flat
rocks to keep it from floating up.
We top it off with water hyacinths (and blocked from plugging up the outlet).


k30a

(O3raledale) writes:

hello all, I'm new here and new to pond building. I'm building a bio-filter and
need to fill it with lava rock. I went to the pond store today and they want
$40.00 a bag for small lava rock. Could I just use new BBQ grill lava rock? It
would be alot cheaper and isn't all lava rock the same?

Lava rock has a bad area to volume ration and a bad area to weight ratio.
Better to use something plastic...

Sean Dinh writes:

One thing great about TT is that the water get good oxygenation from flowing
down non submersed lava rocks. Do you suspend the screening horizontally as to
replace the lava rocks? Or are the screenings submersed? If the former, how many
layers do the water fall through before hitting the water level?

I use a spraybar in the one of the filter chambers. Doesn't take much pump
output, I think I have three 1/8" holes, pointed to get the water circulating
around.

I added it one hot summer when I noticed the fish distressed in the morning,
gasping at the surface. Solved it completely :-)

HTH