Adding a tank to an existing setup (cycle)

[beerking]

I have a 180g tank with a sump and refuge. Probably (minus rock) 225g of water volume. Its a very mature reef and I'm adding a 125g tank with base rock and some DIY rock. I have added bagged sand and was wondering on the cycle. Is it necessary to add shrimp and let them rot and do the whole cycle? There would be an influx of bacteria from the existing tank setup once added.

[beerking]

I know there's a lot of multi linked setups here. I didn't cycle my fuge when I added it. Same thinking no? The base rock, diy rock, and non live sand make me nervous though.

[jdezek]

From my understanding any time you add something new it will cause a cycle, might be unnoticeable. If your talking of another complete set up with new sand and rock it will cause a pretty good cycle because there is no bacteria in those. You could do it in stages to keep it from doing a big cycle. Start with the water then add some sand let it go then add the rest of the sand let it go then slowly add the rock.

[Just Jim]

I'm adding a 150g setup into mine as we speak. I've been using the waste water from my water changes and adding it into the 150g weekly. It still will take time to process though. I'm not sure I'd risk not cycling.

[tmz]

I've added tanks to my system over the years. I have 7 plus several refugia integrated on the main system.
I would cure and seed the base rock before adding it to the system and check the during water for leaching phosphate as well as ammonia ,nitrite and nitrate .before putting a large quantity of it into the main system.

[bertoni]

I would just set the system up and let it run for a bit. If no ammonia shows up, you could add a bit of fish food now and then, to see how the filter is doing.

[beerking]

There's no filter. The skimmer is in the fuge so I need to plumb it in to get filtration. I put some mysis in there to rot a bit. I like the idea of adding "dirty" water from my other tank's water change. Will that be enough to add the good bacteria?

[bertoni]

The new tank will get some bacteria that way. I don't know whether it'll be enough to make a difference. Most of the ammonia consumption is done by bacteria living on the surfaces in our tank.

[tmz]

Not much bacteria is in the water; ammonia oxidizing bacteria colonize surface areas. The old water brings in decaying matter though without the bio filter to handle it.