Pulverized Limestone

[jubbin2001]

Found this at my local Menards and was thinking I could use it as "filler" for my sand bed.
https://www.menards.com/main/search....ized+limestone
It looks safe enough, except I see there is copper listed on the SDS. It is listed at .00008 percent is that enough to be concerned about?

[jubbin2001]

I see others are using a similar product with pretty good results. After much rinsing here is a the product, its SDS, and a photo of the grains next to some oolite.
http://imgur.com/a/u00EtPz

[bertoni]

It's probably safe enough. I wouldn't worry all that much.

[jgraz]

So you want to use lime meant for your yard that may or may not have enough copper(known reef no/no) to add as a filler for your sand bed?

Why?

[jubbin2001]

Because I thought it might be fun ? I was kind of wondering if anyone else tried it tbh. I had heard that others were being successful with pulverized lime as a substrate.
As of now, it's actually going to be more of an experiment. I'm not a chemist, so determining how much .00008 copper is, is a little outside my wheelhouse. Also, this in being put into an empty 125g tank that has no live stock, no live rock(dead rock that I gave an acid bath too will be in it), and no live sand. I plan on letting the tank cycle, during which I will be testing the parameters to see if it's a viable option. Since I want a 4-5 inch sand bed, if I can use something else for the bulk of it and save $300, why not? If it's not leaching any pollutants into the water and I'm not recklessly killing livestock, why pay $25 for a 30lb bag when I can pay $4.50 and get a 50lb bag? Of course after I rinsed it all off, I would say I only got between 25-30lbs of usable material. I plan on doing a full barrage of tests including, but not limited to: making sure PH is stable, phosphate and nitrate stay low, and no copper can be detected in the water column. I would monitor them for at least 2 weeks after the cycle before I would even attempt to put something in there...and if I do decide to do that (if all parameters are in check) it would probably only be a few hermit crabs or a couple snails. If it ends up leaching copper into the tank, my hypothesis is that the cycle won't even get started because the copper will kill all the bacteria. I'm just looking for a different solution to save $300 on substrate.

[bertoni]

The copper is unlikely to be an issue. There are other possibilities, but it's not cost-effective to test for safety.

[jubbin2001]

To be clear - I am talking about limestone and not "lime". According to what I have read, limestone shares the same chemical makeup as aragonite (calcium carbonate) except it has more magnesium. Apparently the structure of the limestone is also different which causes it not to dissolve like aragonite does. I'm sure there is much more to it, but again, I am not a chemist/geologist.

To me, based on the information I have read, it stands to reason this would make limestone a viable option when talking about the depth of sand bed I am looking for.

Just from a cost perspective - the 7 bags/350lbs of pulverized limestone I have washed has cost me $33.79. To get the same depth with oolite aragonite it would take 12 bags with a cost of $283.61.

So I am thinking why pay 8x the cost if there is another alternative that can achieve the same results.

[bertoni]

Yes, limestone is calcium carbonate. It's a different crystal form, and it will contain some impurities, particularly magnesium. It's less soluble than aragonite, which is mostly irrelevant, and it might be a good grain size or not, depending on your goals. It's very likely safe, but it could have some contaminants that cause problems. I haven't heard of any, though. You might want to see how it looks in a tank, too, before buying much.

[jubbin2001]

Here is the pulverized limestone in the tank. It's a little cloudy because I added water tonight. It doesn't look too bad, but I will be topping it off with some aragonite, just so as things progress it breaks up the tan.

http://imgur.com/a/XikQxGX

[jubbin2001]

Ok so it's been 5 days since I added water to my tank. I ended up using 400lbs of the pulverized limestone from Menards and 40lbs of CaribSea Ocean Direct Live Sand.

Here are the parameters thus far:
Copper - Undetectable
Ammonia - 5ppm
Nitrite - 3ppm
Nitrate - 40ppm
Ph - 8.2
dKH - 10

Used brand new Salifert test kits for the results. So far it looks like the tank is cycling and everything is on track.

[bertoni]

That seems like good progress!

[jubbin2001]

bertoni - Agreed. I think I might try some Microbactr 7 and see if there is a change in the ammonia readings. Although I am inclined to think that standard tank cycle could mask the results. Since I started with a lot of "dead" rock and a lot of "dead" sand, I was thinking a little seeding couldn't hurt...or at the very least it'll be a waste of money

[jubbin2001]

I did end up adding some Microbactr7 on day 7 since I was starting with a lot of dead material (the rocks and 450ish lbs of pulverized limestone). Here is the update 9 days after adding water:
Copper - Undetectable
Ammonia - 0 ppm
Nitrite - 3ppm
Nitrate - 80ppm
Ph - hovering between 7 and 8
dKH - 9


A little about how I started this tank cycling:
I did phantom feed (a pinch of flakes) for the first 3 days after adding water. I did not test the water during that time for ammonia or other chemicals. On the 4th day I did test and saw that the ammonia had reached 5ppm. At that point, I stopped phantom feeding. I am sure there was still some "left over" material on the walls that I didn't scrape off that contributed to the ammonia amount. I didn't completely bleach and sterilize the tank after I last drained it, though I did clean it with rags and swished around fresh water in the tank before soaking up as much as I could. The little water that remained just evaporated out. This is a 6ft tank and is not really something I can move myself, so no, it was not 100% rinsed and sterile .

Observations:
1 - It appears the tank is cycling, though at a faster rate than I expected. Unsure if it was adding a combination of Microbactr7 and 40lbs of live sand, could be an effect of one of those products over the other, is what could be called "normal" (though for a 125g tank with almost all "dead material" I don't see that being the case), or could be some other unknown variable.

2 - Rocks and sand bed are covered in diatoms. Over the course of 3 days they went from small patches on the sand bed and rocks to almost complete coverage of rocks, substrate, heaters, pumps, and glass. Thought not what I would call " excessively thick", they are still present and very noticible.

3. Gas pockets have started forming in the 1ish inch of CaribSea live sand I added to the top of the limestone. Unsure if it's due to bacterial population, if some of the air that was trapped in the limestone when I filled my tank is making it's way up, or if is being caused by some other unknown variable.

I do think I will be doing a water change soon as I still seem to have a high amount of nitrite. I also would like to drive the nitrate down a bit. Even though I am working to establish a DSB, I don't think the answer is leaving the tank saturated with nitrate.

I will continue to monitor over the next few weeks as the cycle continues, but as far as I can tell this particular limestone is working as I was hoping it would. I do hope this trend continues

[bertoni]

That all sounds normal to me. For #3, I have never been sure, but I suspect photosynthesis or anaerobic decay.

I agree that driving the nitrite down might help speed the process, but it's a personal choice. Just waiting is fine. The nitrate won't affect the speed of cycling, but removing some of it might help with the photosynthetic pest, whatever it is.

[jubbin2001]

It's been another 10 days since my last post so, I thought I would update.
Diatoms have almost all disappeared. some very light residual spots are still visible, but the "bloom" has very much dissipated. My lights have been on for the entire cycle...I hated staring at a black tank. I'd rather see a clean tank of rock and sand than an unlit tank. The blues are on for 12hrs and whites/blues are on for 10. No green algae as of yet, though with the nitrates being high, that's probably only a matter of time.

Parameters:
Copper - Undetectable
Ammonia - 0 ppm
Nitrite - 0ppm
Nitrate - between 50 and 100ppm ( I forgot to mention in my original post that I didn't get a Salifert Nitrate test kit and I was using an API. I have now since upgraded to the Salifert.)
Ph - is still hovering between 7 and 8
dKH - 9

I have not done a water change yet, but it looks like a 50% is due. Once I let that sit a couple days I will retest Nitrate and see what I come up with. It looks like I had a pretty successful cycle. Now to find some crabs to put in.

[jubbin2001]

Update on the tank - Never did any water changes and all parameters have been stable for the last coupe weeks:
Copper - Undetectabe
Ammonia - 0ppm
Nitrite - 0ppm
Nitrate - 20-30ppm
Ph - 8
dKH - 9

Tank is ready for inhabitants, so the cerith snails, nassarius snails, and crabs are inbound.

[bertoni]

That sounds like good progress.