[Ann]

What are those rocks called that you have in https://m.youtube.com/c/opaeula and where did you buy them?
Thank you,
Ann

[odin]

Hi Ann, The rocks i used in my Opae ula tanks is called 'ocean rock' over here in the UK, its made up mostly of limestone so it buffers the water really well and stops the tank water becoming acidic. You guys in the USA call it 'Texas holey rock' so you can buy it from ebay or aquarium stores pretty easily. Just be sure you buy the ocean rock/Texas holey rock which is dead ocean rock and NOT the live rock, The live rock that gets used in marine tanks looks very similar but has a lot of living organisms and other living creatures living inside. The level of salt in our brackish Opae ula tanks is not enough to support the living things in the live rock so it all dies and will flood your tank with Ammonia.

If you need any help finding some just ask and I will try and help

[Ann]

Ha! Ha! We sure have a funny name for it in the States. I never heard of it. It looks so nice in your tanks. It has an important purpose. Thank you for answering. I know that I have a thousand questions. I'll look for the rocks.
Thanks again.
Ann

[odin]

No worries, ask away!

[Ann]

Thank you. That's very generous.
Ann

[Ann]

Hi Odin!
I did check out the rocks. They were on Ebay just as you said. Expensive little gems. There were also other sites that sold synthetic rocks. They serve no purpose and looked like hunks of cheese. I'm going for the real thing. Thank you.
Ann

[odin]

Yes they can be a little expensive but they look really nice

[Ann]

They're absolutely beautiful! They create serenity in the aquarium..
Ann

[Ann]

How would I know whether the ocean rock is alive or not? Are they different looking? Would the seller tell me?
Ann

[odin]

Hey Ann, if you buy live rock it will be kept in water for storage and look slimy, will be covered in organic matter and other life, this is to keep all the organisms etc alive. When you put live rock in brackish water the salt levels are not high enough to support the marine organisms and plantlife. Same goes for live sand, when it all dies off you will get a huge amount of ammonia in the tank. This is what you are trying to avoid.

Here is live rock, just like what is in the sea:

image.jpeg (142.67 KiB) Viewed 14513 times

Below is ocean rock/Texas holey rock, it's clean, dry and cured. There won't be anything living on/in it that will die as its been out of marine/ seawater for a very long time and been scrubbed clean. This ocean rock is what's also used in freshwater cichlid tanks too. It's popular because it buffers the water perfectly stopping it becoming too acidic.

Here is your ocean/Texas holey rock, in shops it will just be in a bin/box all dry:

image.jpeg (205.31 KiB) Viewed 14513 times

Both types have very different purposes depending what sort of tank you are setting up, how ever live rock/live sand should only go in marine tank setups. Sellers will know exactly what you are asking for, that and live rock is very exspensive compared to ocean/Texas holey rock.

Any more questions then ask away.