Adding rock to an established tank

FishyFish · Mar 9, 2019

So I got impatient when I started my tank, it's a 30 gallon cube with around 20 pounds of rock in it. I'd like to finish what I started and add another 10-15 pounds but now that I have fish and tons of hitchhikers I'm not quite sure how to go about it. Would it be safer for my inhabitants to add more live rock or should I go with dry rock? Is there any kind of rock that doesn't need to be cured first?

I'm also curious about glues, I bought some super glue gel to glue my rocks together but chickened out and didn't end up using it. Most of the threads I see about gluing rocks are gluing dry rock, are there any options for gluing live rock in an established tank? I want to add a sand sifting goby and maybe a wrasse or two so I want my 'scape to be rock solid (har har!) Any tips? Thanks!!!

Bleigh · Mar 9, 2019

I have no knowledge about the first half of your question, but I use putty to put things together in my water. I got it from my lfs and it comes in a couple of different colors. You cut off a piece and work it between your fingers until the two compounds mix. It cures in a few minutes in the water. Word of warning though, dont use your kitchen knives to cut off the piece of putty. The putty cured on my knife while I was trying to wash it off.... that's one knife ruined, hopefully one less ruined for you.

AdamPhe · Mar 9, 2019

I did the same thing. I added a few pounds of dry rock at a time over a couple months. That worked for me.

Fourstars · Mar 9, 2019

I’m always cooking a few pieces of dry rock in my tank for some future tank. While I have glued a few pieces with underwater epoxy there is something to be said about building a lose structure. Makes life much easier if you need to work on a piece to manicure it. If you started with dry only then I would get a nice piece of live from the LFS or a buddy. It sure speeds up the maturity of the tank.

FishyFish · Mar 9, 2019

Bleigh said:
I have no knowledge about the first half of your question, but I use putty to put things together in my water. I got it from my lfs and it comes in a couple of different colors. You cut off a piece and work it between your fingers until the two compounds mix. It cures in a few minutes in the water. Word of warning though, dont use your kitchen knives to cut off the piece of putty. The putty cured on my knife while I was trying to wash it off.... that's one knife ruined, hopefully one less ruined for you.

Thanks! I'll see if my LFS has any putty, that sounds a lot safer than glue. I promise not to use any kitchen knives on it.

Fourstars said:
I’m always cooking a few pieces of dry rock in my tank for some future tank. While I have glued a few pieces with underwater epoxy there is something to be said about building a lose structure. Makes life much easier if you need to work on a piece to manicure it. If you started with dry only then I would get a nice piece of live from the LFS or a buddy. It sure speeds up the maturity of the tank.

I started with 20 pounds of live rock and the tank has been going for 3 months now. I'm wanting to glue the rock because I've been thinking about putting in an arch, they look really neat!

jrill · Mar 9, 2019

The super glue will work in water too. Even better to use both. Use super glue to secure the putty to the wet rock.

Seamore2001 · Mar 9, 2019

For adding the live rock, it kind of depends on how the LR was treated prior to you purchasing it. If it's been fully cured and hasn't been out of water in some time, it should be fine to add to your tank. If it hasn't been cured (i.e. taken from the ocean, kept in a box out of water for a few days wrapped in damp newspaper) then it'd need to be cured.

Of course, given the near impossibility of getting LR from the ocean short of ordering it from Florida, I doubt you're getting stuff that hasn't already been cured in a tank somewhere. If you're buying it wet, it is probably fine to put into your tank. One quick way to tell if the LR is cured is to give it a sniff test: if it smells like the ocean shore at low tide, it's likely fine. If it smells like rotten eggs (sulfur), it needs to be cured.

The issue with adding LR to a tank is that during the transport process (as described above) you can have massive die-off. If that happens you will need to "cure" the rock to get rid of whatever is on and in the rock that has died, before adding it to your tank. If you're fortunate enough to get real ocean LR and it has gone through this process, you'll need to cure it first in a separate container outside of your tank.

norfolkgarden · Mar 10, 2019

Everything already suggested. [emoji846]

Also be ready for your skimmer to possibly go nuts after you add the reef putty.

If you don't have a skimmer plan on doing a large water change at the end of puttying. (Is that a word?)

And maybe another the next day.

I usually try to limit it to puttying in 4 or 5 frags a day in a week and then do a good size water change.

No skimmer.

maevepotter · Mar 10, 2019

Can you really just put dry rock in an established tank without curing? I always heard about leaching etc. I got some cheap rock on Amazon that I want to get going, but it was quite dusty. What method would you use?

norfolkgarden · Mar 10, 2019

maevepotter said:
Can you really just put dry rock in an established tank without curing? I always heard about leaching etc. I got some cheap rock on Amazon that I want to get going, but it was quite dusty. What method would you use?

It is remotely possible that the dry rock is full of phosphate.

I would rinse it off well with tap water and then let it soak in a 5 gallon bucket of tank water for a day before adding it.

The dried rock I jad left over that I added straight to the tank ended up with a lot of bubble algae.

It would help to cure it in a tank without a light on it for at least a few weeks.
And test for phosphate before adding to the tank.

I added about 10 pounds just dried rock straight to the tank.
But all I have is softies, hammers and fish.
Nothing that gets too cranky. [emoji846]

FishyFish · Mar 11, 2019

Seamore2001 said:
The issue with adding LR to a tank is that during the transport process (as described above) you can have massive die-off. If that happens you will need to "cure" the rock to get rid of whatever is on and in the rock that has died, before adding it to your tank. If you're fortunate enough to get real ocean LR and it has gone through this process, you'll need to cure it first in a separate container outside of your tank.

If I went this route, I would be buying the rock from a tank at my LFS, bringing it home in a bucket full of water, then adding it to my tank as soon as I got home so it would be like 30 minutes tops tank to tank. Is this a short enough time period that my tank should be safe? If it's too risky I'd rather just cure the rock and wait before adding to my tank. Sorry if this is a dumb question, but I want to be extra safe since my tank is already inhabited.