How long does it take the tank to compensate for the added bioload of fish before adding additional fish? My tank was up for 8-10 weeks before I added my first 2 fish this past weekend. How long should I wait before adding any additional fish? I was figuring 2-3 weeks between adding fish?
How long to wait between adding fish.
- Thread starter BigCity
- Start date
TheFishTeen
New member
There are a ton of methods to add new fish but your safest bet is to test your Nitrates No3/Nitrites No2. Once they are Zero (0.ppm) you're good to go. After you add a fish they might go up temporarily. During that period do not add a fish. 2-3 weeks is definitely enough time. When they hit zero (0.ppm) you can add another fish. Keep in mind your skimmer may need to be adjusted as your bio load increases.
Since Nitrite is the result of ammonia, if you test Nitrite and It comes out above zero (0.ppm), you know there is ammonia in the aquarium and that could kill your fish. Nitrate is stage of conversion in the nitrogen cycle where the toxins from the ammonia/nitrite becomes less toxic, but at very high numbers NitrATE is still dangerous. If you test your Nitrates .2 and consistent water changes don't make a difference, you should be able to add another fish even though it does not read zero.
Some tanks never hit Zero Nitrate.
Since Nitrite is the result of ammonia, if you test Nitrite and It comes out above zero (0.ppm), you know there is ammonia in the aquarium and that could kill your fish. Nitrate is stage of conversion in the nitrogen cycle where the toxins from the ammonia/nitrite becomes less toxic, but at very high numbers NitrATE is still dangerous. If you test your Nitrates .2 and consistent water changes don't make a difference, you should be able to add another fish even though it does not read zero.
Some tanks never hit Zero Nitrate.
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It's a 120g with 40g sump, have probably 150# of live rock between the sump and tank, 4" deep sand bed, also have chaeto and mangroves in the sump with a reactor running carbon and also one for GFO (isn't running yet, may not need to with the tangs). I have a kole tank and a sailfin tang (yes I know I will be upgrading the tank size down the road), both about 2-3" in size. I know I may have made a mistake adding the tangs first, but you have to learn one way or another.
I haven't been QT'ing I know, I know, but those were the first fish and I don't have the means currently to QT. Although I am lucky enough to be 30 minutes from premium aquatics so I feel a bit better about the quality of product compared to dealing with shipping, etc (not that it necessarily gaurantees anything).
I haven't been QT'ing I know, I know, but those were the first fish and I don't have the means currently to QT. Although I am lucky enough to be 30 minutes from premium aquatics so I feel a bit better about the quality of product compared to dealing with shipping, etc (not that it necessarily gaurantees anything).
greech
New member
Maybe I missed it but how old is the tank and do you have a skimmer?
If the tank is new you might want to give it some more time and test. Feed the fish well and test more. A month or 2 may be a better time frame to shoot for. IME the newer the tank, the longer you should wait between additions. If you happened to start with really well established rock that came out of a healthy system you might be looking at shorter intervals.
If the tank is new you might want to give it some more time and test. Feed the fish well and test more. A month or 2 may be a better time frame to shoot for. IME the newer the tank, the longer you should wait between additions. If you happened to start with really well established rock that came out of a healthy system you might be looking at shorter intervals.
First post called out the system has been running for about 10 weeks now, and thanks for the reminder I forgot to mention that I do have a Aqua C EV180 protein skimmer. Started with dry rock seeded with about 50# of live rock.
lordofthereef
One reef to rule them all
There isn't going to be a magic number here. Once the fish have been added, make sure you are feeding normally and taking water quality tests. You shouldn't have detectable levels of ammonia and nitrites. If this is the case, IMO, you are safe to add more.
Remember to quarantine your livestock though!
Remember to quarantine your livestock though!
