Seeding old live rock


New member
So I just set up a new aquarium using some dried old rock I had (very dead). I figured when I added the live sand it would seed the rock and I would be ok but now I am second guessing that.

Will live sand seed dead rock?

If it will not do the aquarium cycle kits that are sold (like bio-spira) do the same thing? I am kind of worried about not having some of the fun little hitch hikers tag along...

What are my other options to seed? My local shops arent carrying LR right now because there is a sales ban currently and I am not part of any local clubs because of the current situation. I was considering posting on the livestock threads here to see if I could buy a few small pieces but they all seem dead or not dealing in rock either. I read that if you buy inverts with shells some of the bacteria can transfer over but that it was a slow process

Thanks for all the help!

Michael Hoaster

Registered Seaweedist
Premium Member sells farmed live rock from Florida. Their prices include shipping and are very reasonable. You can buy as little as ten pounds, which would be perfect for your situation.


Super Best Friends!
Premium Member
I've used jump start bottles that help...forgot the brand, but it was bought refrigerated from a LFS.

I wouldn't rely on live sand for your seed. I'm sure there's some viable bacteria in the sand, but probably not enough. My recommendations, in order:

Get real live rock, let it cycle, profit. I haven't seen it in a LFS in a LONG time, so good luck.

Get a couple of small rocks and a big ol scoop of sand from a well established tank. Toss it into your tank and let it grow. Toss in some fish food from time to time during the cycle to promote bacterial growth. Toss in a bacteria jump start for an added bonus...$20 can't hurt.

Get a couple of small, established the above things

Get a scoop of the above things

If all that isn't available, add a bacteria boost, feed the tank to facilitate growth.

Remember, the jump start still takes time to properly cycle. Take things slow no matter how you attack it.


Staff member
RC Mod
Back in the Jurassic we used dead dry rock and dead sand and just started with a gallon of water from the fish store display tank. It was pretty clean, as display tanks tend to be. Butt we've found better and faster ways since.


Well-known member
I start all my tanks with dry sand and rocks. It will become live soon enough.



Premium Member
Of course you're second guessing. No critters, creatures, flora or fauna will be coming out of your dead rock but will contimue to ome out for years to come -- when you buy some real reef rock. Think of it as an investment if that helps. It's absolutely cruel to start a reef without it to the inhabitants you purchase. It is a giant filter in itself. Tanked only works for athletes and celebrities who can't be so bothered with actual reef life and conditions.


New member
The bacterial starter bottles worked really well for me. I was able to cycle my tank with dry rock and live sand within two weeks! I used a raw shrimp as an ammonia source.