Might be a stupid question...Can I use the lava rock sold for bbqs as media for my filter? Seems much cheaper than bio balls.
BBQ Lava Rock?
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Sure. But lava rock isn't as highly thought of as it once was as bio media. Years ago people thought because of it's large surface area it would be great, but soon realized the pores clogged pretty fast. People moved to Trickle Towers after the lava rock thing. You use smoother rock which stays cleaner so more bacteria and the increased O2 fires them up so about 10x better bio conversion. After that were Shower filters but that's more for very high fish loads.
Smoother rock like crushed limestone?..What rock would you recommend for a trickle filter?
I'd use whatever was laying around the yard. Limestone can be rather soft, not sure how bacteria would react to possible surface pH issue of some limestone. I sure wouldn't go out and buy limestone unless you wanted to try it. I'd use any hard, non-porous type rock. I generally use river rock because I use it when building the pond.
If you do want to experiment it is super easy, can be done in a 5 gal bucket or small test pond. Need some water, pile of rock, pump (any flow) pushing water over the rock, some regular pure ammonia from the cleaning department of many stores and an ammonia test kit. Add ammonia and test that you get it to some reasonable level (too high and bacteria can't/slow grow). Run the pump and test ammonia each day. Depending on temp should take a few days, a week max, to see ammonia reducing. You can test the rest of the cycle if you like, can add more ammonia and watch how fast it goes down, etc... Best to do this in a garage, under a tarp in the shade, block out as much light as possible so you don't get algae which eats the ammonia and throws off the test.
Bottom line with all bio filters...you have to test ammonia to know if it's working. Most Water Gardens don't have fish loads anywhere close to actually needing a dedicated bio filter. I've heard people add them as "insurance" but it remains the same, must test to know whether you actually have insurance. Or just add some because you want to which is of course perfectly fine...it's a hobby...have fun.
I do sometimes fill the waterfall catch basin with river rock, so kind of an underwater TT. Not as efficient as above water, but still gets pretty good O2 and keeps rocks pretty clean. Downside is underwater isn't as good for growing string algae. Above water can get string algae and clear a green pond. Less bacteria but algae consumes ammonia so no big loss in most cases.
If you do want to experiment it is super easy, can be done in a 5 gal bucket or small test pond. Need some water, pile of rock, pump (any flow) pushing water over the rock, some regular pure ammonia from the cleaning department of many stores and an ammonia test kit. Add ammonia and test that you get it to some reasonable level (too high and bacteria can't/slow grow). Run the pump and test ammonia each day. Depending on temp should take a few days, a week max, to see ammonia reducing. You can test the rest of the cycle if you like, can add more ammonia and watch how fast it goes down, etc... Best to do this in a garage, under a tarp in the shade, block out as much light as possible so you don't get algae which eats the ammonia and throws off the test.
Bottom line with all bio filters...you have to test ammonia to know if it's working. Most Water Gardens don't have fish loads anywhere close to actually needing a dedicated bio filter. I've heard people add them as "insurance" but it remains the same, must test to know whether you actually have insurance. Or just add some because you want to which is of course perfectly fine...it's a hobby...have fun.
I do sometimes fill the waterfall catch basin with river rock, so kind of an underwater TT. Not as efficient as above water, but still gets pretty good O2 and keeps rocks pretty clean. Downside is underwater isn't as good for growing string algae. Above water can get string algae and clear a green pond. Less bacteria but algae consumes ammonia so no big loss in most cases.
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The textbook answer always was the pores would clog and go anaerobic, kill your fish and steal your first born Son on the eve of the full moon but I was always suspicious it was an old wife's tail. Inside the pond it might give off some hydrogen sulphide , but in a trickle or a wet/dry filter, not so much.
if it does clog up, you can always rinse it and burn off the crude in the bar-b-que, lava rock isn't going to melt!
if it does clog up, you can always rinse it and burn off the crude in the bar-b-que, lava rock isn't going to melt!
Yeah.
Back in the day no one was really concerned about the clogged pores on these causing H2S or anything like that. It was purely that the clogged pores reduced surface area by a lot. So it was suppose to be providing more surface area it ended up being less than regular rock. Back in the day we were are crazy for surface area.
Can be cleaned, but kind of the point of a TT is that it doesn't need cleaning. And cleaning was a big problem with many bio designs. A filter that needs cleaning will have a declining efficiency as it clogs. Ammonia has to be removed at a constant rate. So that meant the filter had to be over sized and of course not cleaning in time meant lost fish. The TT and Shower filters fixed that problem and was as big a plus as their efficiency.
But of course most Water Gardens don't need bio filters so it doesn't really matter what the media is, whether it's cleaned or not. Algae will take care of the ammonia...even if it never gets any credit.
Back in the day no one was really concerned about the clogged pores on these causing H2S or anything like that. It was purely that the clogged pores reduced surface area by a lot. So it was suppose to be providing more surface area it ended up being less than regular rock. Back in the day we were are crazy for surface area.
Can be cleaned, but kind of the point of a TT is that it doesn't need cleaning. And cleaning was a big problem with many bio designs. A filter that needs cleaning will have a declining efficiency as it clogs. Ammonia has to be removed at a constant rate. So that meant the filter had to be over sized and of course not cleaning in time meant lost fish. The TT and Shower filters fixed that problem and was as big a plus as their efficiency.
But of course most Water Gardens don't need bio filters so it doesn't really matter what the media is, whether it's cleaned or not. Algae will take care of the ammonia...even if it never gets any credit.
I've been using it ( landscape lava rock, same as BBQ rock) for several years in both a canister filter on my turtle tank and in a skippy style drum filter on my pond, I've never seen this "clogging" issue being described. I use a pre-filter box before my pump so the heavy stuff gets filtered out before even reaching the lava rock. I quick backwash rinse takes care of any build up issue, if any.I wash my my drum filter down when I close up the pond for the winter, starts up fresh in the spring.
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My lava rock, in Arizona, was in a large square plastic tub surrounded by a metal frame. I think it held 400 some gallons. You see them here and there. I covered the outside with rocks had the water go in the bottom out the top. It made a great water fall.
I would just turn it off, use a garden hose with nozzle spray water from the top down, wash out the pond dirt. Ran it that way for around 9 years.
I would just turn it off, use a garden hose with nozzle spray water from the top down, wash out the pond dirt. Ran it that way for around 9 years.
sissy
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Lava rock is old fashioned but it works and even The pondhunter and eric the pond digger still use it .I buy the landscape lava rock at lowes .But had a friend in Hawaii that sent me some from there.I pit mine in dollar store laundry bags and then put it in the filter .If I need to pull the bag for a quick rinse it is easy .I just fill a 5 gallon bucket with water and a little peroxide and do a dip and swish and then bucket of water goes in my garden .The best fish poop veggies ever
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Meyer Jordan
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A little clogging of Lava Rock will actually provide an added benefit. Anaerobic conditions in the clogged areas provide de-nitrification helping to keep Nitrate levels down.
All you really want is something with a lot of surface area that the bacteria can grow on. For me that is plastic snow fence. A fifty foot roll cost $10 dollars.
sissy
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I love my lava rock ,son bought me bio balls and I have yet to use them and they have been sitting around for 5 years now
Mmathis
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One difference with having lava rock in a TT vs
Now, if your question has to do with....is the BBQ rock "DIFFERENT" from regular lava rock, as in treated with any chemicals.....? That is a good question and I don't know the answer.
And BTW, there really are no stupid or dumb questions! If you don't know something, that makes it a very good and valid question! Never be afraid to ask questions....for every question someone asks, there are dozens of other people out there who have the same question but are afraid to ask.
What kind of filter do you have? I would be sure to rinse it very well before using it, and of course, you'll be rinsing/cleaning your filter media anyway, so as long as you don't give it a chance to get really dirty, it should work OK.
Now, if your question has to do with....is the BBQ rock "DIFFERENT" from regular lava rock, as in treated with any chemicals.....? That is a good question and I don't know the answer.
And BTW, there really are no stupid or dumb questions! If you don't know something, that makes it a very good and valid question! Never be afraid to ask questions....for every question someone asks, there are dozens of other people out there who have the same question but are afraid to ask.