Cycling a large tank

dnledman · Dec 12, 2024

So I have been keeping saltwater fish tanks for the better part of 20 years. Got my first big system though, roughly 210 gallons for the whole thing. I used some dr. Tims, some live rock, mostly base rock and now have two clowns in it. Ammonia is at zero and has been there for two weeks. Tank is 3 weeks old, never tested the first week.

Does it take longer to cycle such a big system or has the dr. Tims and live rock knocked it out of the park and I can start adding more fish?

fishywishy · Dec 12, 2024

If you added the proper amount of ammonia and bacteria for your tank size it should cycle in the same amount of time as a small tank.

If you cycled it properly you can start adding more fish. Even though the tank is massive still take it slow.

PharmrJohn · Dec 12, 2024

fishywishy said:
If you added the proper amount of ammonia and bacteria for your tank size it should cycle in the same amount of time as a small tank.

If you cycled it properly you can start adding more fish. Even though the tank is massive still take it slow.

Agreed. As you add fish the microbiome will catch up as it would in any tank. The end balance will take longer overall, as it'll take longer to bring stocking level up to where you want them comparitively.