“Cooking” a mix of dry rock and established rock…

[WhatCouldGoWrong71]

So, back in June I abandoned an idea I had, which left me with about 75 pounds of that purple petco rock. So I tossed it in a brute, a long with lots of stuff along the way (anything with life on it from my established tank that came out of it went in the bin, even filter floss, when I would dump one in, I would pull the last one out, and so on…) I wound up pulling 4-5 decent size rocks out of my system and put them in the same brute. I also put a piece of raw shrimp or salmon in the brute weekly. Along the way I have tested for PO4, and man I can so see why that virgin dry rock is a pita. I’m nearly 6 months into this cool and I tested the PO4 again yesterday and it was .31. I have changed the water about 8 times, and based kn some feedback from and dosed LC multiple times. I’m starting to wonder if these rocks will ever leach all the PO4 out. My concern is that I wonder if the matured rock I put in there is absorbing the PO4 now. I’m going to pull it and put it in its own bin. How long do you think I have to wait to test for PO4 to know if these established rocks are now going to leach PO4?

I have tons of amphipods, stars, worms, etc living in this bin. I keep a heater and flow in it. Zero light, so all the rock looks the same as the day I put it in there. Also, If I dose Dr. Tim’s ammonia, how much would I need to dose and how long would. I have to wait to test to ensure I have a good level of bacteria on the rocks? I just can’t believe the level of PO4 still…

 

[jda]

Aragonite, calcite and dolomite will all eventually unbind all of the phosphate - it can take a long while so keep at it. Once the po4 level gets low, it takes even long since you are then unbining the stuff way into the middle. Without corals in there, you can get aggressive with the LC - I do.

All of the rock will end up at the same binidng level if you give it enough time - assuming that the structure is the same (which is not a good assumption). In any case, if you get the water level po4 low, all rocks will be low too.

You can stop changing water to lower po4 - just does not move the needle since the mass is in the rocks.

If you want more than bacteria on the rocks, then light will be needed. Film algae, matting bacteria, coralline, etc. all need right. You need more than ammonia oxidizing bacteria and some heterotrophs to keep the uglies off of the rock.

Some sort of fish food is fine to feed what is in there - those shrimp should work. The juice from frozen food is likely fine too.

 

[WhatCouldGoWrong71]

Aragonite, calcite and dolomite will all eventually unbind all of the phosphate - it can take a long while so keep at it. Once the po4 level gets low, it takes even long since you are then unbining the stuff way into the middle. Without corals in there, you can get aggressive with the LC - I do.

All of the rock will end up at the same binidng level if you give it enough time - assuming that the structure is the same (which is not a good assumption). In any case, if you get the water level po4 low, all rocks will be low too.

You can stop changing water to lower po4 - just does not move the needle since the mass is in the rocks.

If you want more than bacteria on the rocks, then light will be needed. Film algae, matting bacteria, coralline, etc. all need right. You need more than ammonia oxidizing bacteria and some heterotrophs to keep the uglies off of the rock.

Some sort of fish food is fine to feed what is in there - those shrimp should work. The juice from frozen food is likely fine too.

Interesting. I guess there is no reason to fear the label where it says “don’t bring the PO4 down to quickly…”, lol. So if one had a less than desirable tank that would never be sued for a display, one could transport the rock to that to assist with lighting then. I could reclaim the brute as I was going to have to go buy another one. Since I will be adding light, the. I guess that doesn’t matter?

 

[jda]

You can just put a shop light over the brute if you want. None of that stuff needs a lot of light. I have a 48" LED Shop light over my 72x30x30 FOWLR and it grows coralline like crazy.

Lowering too fast is for corals. You are all set there.

The last time that I got used live rock, I put in a rubbermade. Waited a few days and got flashing number on my Hannah, so over .6, but the color in the vial was super-duper blue. I poured in like an ounce of SeaKlear and the water got really white. I had a few skimmers on there and few socks with power heads blowing into them through hoses. After the white cleared up, I was down to like .40, or so. ...so another huge addition of LC and it dropped even more. Once it gets down below .1, it takes longer for the po4 to unbind. Don't be afraid to go fast with just rocks.