Dry rock to live rock conversion?

[b4tn]

Just curious. I started with 45 lbs of dry BRS reef saver rock in my 75g reef. Over the past year it has matured well and is covered in red, purple, and green coralline. I seeded it with several chunks of figi live rock from my LFS. I just added another 20 lbs of dry reef saver rock in my 40g sump and now have a total of 65 lbs of dry rock added. What does that convert to live wet rock?

 

[Animagus]

More like wet dead rock IMO. It's going to take a few days for the bacteria to colonize the rock, but once this happens it's essentially live rock now. It's filtration capabilities are not really up to par though. This will take some time before the rock in your DT and the rock in your sump are basically one in the same.

 

[Schreiber]

t's going to take a few days for the bacteria to colonize the rock, but once this happens it's essentially live rock now. It's filtration capabilities are not really up to par though.

Yep, just give it time. There's nothing special about "live rock", it's just already gone through this process. Once the bacteria has reached a certain point on your new rock, it will be functionally identical to the live rock you bought previously.

 

[reeferfoxx]

Don't be surprised if you see another diatom bloom. BRS reef saver rock has silicates.

 

[b4tn]

I think everyone mid understood the question. If I take 65 pounds of dry rock and make it live by seeding it... How many pounds roughly is that if I where to go buy rock that is already live with water weight.

 

[reeferfoxx]

I think everyone mid understood the question. If I take 65 pounds of dry rock and make it live by seeding it... How many pounds roughly is that if I where to go buy rock that is already live with water weight.

If you took 65lbs of dry rock and made it live. It would then be 65 pounds of live rock. If you went and bought rock from a LFS and it were wet then, how are we to know how much live rock you are looking to get?

 

[JoshH]

Too many factors to consider. how porous the rock is, salinity of the water etc. if you took 65 pounds of dry rock and then made it wet "live rock" obviously when you weighed it it would be heavier being wet. how much heavier isn't something I believe there is a calculator for. it is a downside to purchasing live rock. you pay by the pound and pardon the loose comparison but it's like taking a trailer of trash to the garbage dump. If it's been raining you pay more cause it's wet which makes it heavier, dry garbage = lighter load which = smaller cost. Obviously the "wet" live rock is what keeps it live and what makes it extremely beneficial to us as aquarist's. Simplest way to give you a ball park is just take a pound of dry rock you have kicking around toss it in your tank, take it out when it's all live and give it a weigh. That should give you a rough estimate taking into account some of the variables of course. Hopefully that kind of gives you a direction to go in. interesting topic and I'd be curious if you did the little test to see the results

 

[JoshH]

I have always read about the magic ratio of live rock to gallons in system whether it be 1-1 or 2p for every gallon. so does this imply if going with the 1 pound for one gallon rule if I decided to purchase dry rock I could purchase less say "0.75 pounds per gallon" because it would weigh more when it became "live"?

 

[His & Hers. 240 Reef]

I believe that's pretty misleading. The pound per gallon rule. I think it has far less to do with the actual weight of the rock as it has to do with the available surface area of said rock. All rocks aren't create equal. Take a solid five pound cube. You could easily measure its surface area. Now take that same cube and drill 20 1/8" holes straight thru it. Now there would be increased surface area for bacteria to live on yet the cube would be lighter. So the more porous rock the less weight you can get away with.