Ammonia spike in QT tank

john miller

New member
I bought a pair of juvi clowns (1 1/4" & 3/4") last Thursday and have them in a QT tank. The small one is tank bred and the larger is an "I don't know". I've been doing 50% W/C daily. Last night's test showed a reading between .25 & .50. I immediately did another 50% W/C. About 4 hours later it was at .25 again so I did another one. This morning it was still at .25 so I did another one.

My display tank is ready and has been for a few weeks. So which would be the lesser of two evils. Put the fish in the display without fully QT them or continue with the QT and some ammonia levels?
 
IME, ammonia of .25 will not kill fish. It quickly breaks down to nitrites, then nitrates. Don't sweat it, keep doing water changes and you'll be fine.
 
Most experienced reefers don't even check ammonia because it eventually breaks down to nitrates. If you have nitrates, at one time you had ammonia. I can't even tell you the last time I checked the ammonia in my 180, but I check my nitrates regularly. You might want to try another test kit and see if you get the same reading. Either you're still going thru a cycle or something is dead and decomping in your tank to create the ammonia spikes.
 
IME, ammonia of .25 will not kill fish. It quickly breaks down to nitrites, then nitrates. Don't sweat it, keep doing water changes and you'll be fine.


It will only break down if there is an active bio- filtration system and a cycled QT should be able to keep ammonia at 0 for two juvi clowns. Clowns handle ammonia well, but many fish don't. This is commonly missed on a new hobbyists 1st QT. You probably don't have time to cycle a QT now, but never put fish into your DT until they have been fully QTd. You might want to use some ammo-lock, or similar product. It de-toxifies the ammonia. Here's a cut & paste of how I cycle my QT:
In regards to Qt cycling; I've done this for years. Get a HOB filter; I really like Aqua-Clear, they have a big sponge and last forever. Don't use the carbon or ceramic noodles that come with the filter. Also, have some extra sponges on hand, they're cheap. Keep a sponge in the flow somewhere in your DT. When you need a QT or HT, just use the sponge that has been in your main system in your QT filter---the QT will be instantly cycled. When done, toss the sponge and keep a new one ready in your main system.
BTW, Cupramine copper, used in a QT,will not destroy a bio-filter.
 
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Here's a cut & paste of how I cycle my QT:
In regards to Qt cycling; I've done this for years. Get a HOB filter; I really like Aqua-Clear, they have a big sponge and last forever. Don't use the carbon or ceramic noodles that come with the filter. Also, have some extra sponges on hand, they're cheap. Keep a sponge in the flow somewhere in your DT. When you need a QT or HT, just use the sponge that has been in your main system in your QT filter---the QT will be instantly cycled. When done, toss the sponge and keep a new one ready in your main system.
BTW, Cupramine copper, used in a QT,will not destroy a bio-filter.

That is exactly what I did except I used an AquaTech I had laying around. Evidently I didn't have the media in the DT long enough. It was a few days short of three weeks.

This is my first saltwater tank but I'm use to keeping freshwater puffers so when I saw an ammonia reading I freaked. If you see an ammonia spike with one of them your fish will probably die.

So far since I'm changing 50% twice a day it hasn't been over .25 so hopefully my media will catch up soon.
 
MrTuskfish: How long do you leave your sponge in the DT before they are ready to move to the QT?
I always have a sponge in, ready to go. For the 1st one to cycle the QT, I'd guess about 3 weeks. There are a lot of variables that will determine when the sponge has been colonized by enough bacteria to function.
 
Is there anything in your DT? If it's ready, why not just put the clowns in?

I don't see the point in QTing your first fish. Just QT additions IMO.
 
These will be the first fish. I've had my CUC and micro algae in there about three weeks.

My understanding is that I should QT all fish, especially the first. Am I wrong?
 
I'm not saying you are wrong. I've just never QT'd my first fish for a new tank. I only QT new additions so that you don't introduce any new disease to the other fish. Since you don't have any other fish in the DT, I don't see the need to QT. There isn't anything that can harass them and is just as easy to observe them.

If you're having troubles with the QT, I think it would be better to just put them in the DT. This is just my opinion.
 
Is there anything in your DT? If it's ready, why not just put the clowns in?

I don't see the point in QTing your first fish. Just QT additions IMO.

If your 1st fish has a parasite or disease (like ich); then your whole tank is infected and will have to go fishless for 8+ weeks. Also, getting a fish out of your display tank, in order to treat him, can be a major pain.
 
If your 1st fish has a parasite or disease (like ich); then your whole tank is infected and will have to go fishless for 8+ weeks. Also, getting a fish out of your display tank, in order to treat him, can be a major pain.

I'm just saying that if you're having troubles with the water params in your QT and you have a fishless DT.....why not put them in? I'd rather have my fish in a stable tank than an unstable one.
 
I'm just saying that if you're having troubles with the water params in your QT and you have a fishless DT.....why not put them in? I'd rather have my fish in a stable tank than an unstable one.

Okay, I see where you're going now. Just my two cents: once a DT is set up, it is often necessary to tear everything apart to get the fish out. On the other hand, if the QT isn't cycled, ammonia and nitrite will have to be controlled by water changes. (and/ or a product like Ammo-Lock). Nitrates in QT are not a concern. I guess this would just be up to the owner, either would work. Personally, I'd do anything possible to avoid introducing a un-QTd (I'll copyright that word) into DT. There is just too much room for error, such as cross-contamination.
 
So the big question is how long would exposure to consistent 0+ - .25 ammonia readings have to go on before it would be more beneficial to go ahead and move them into the display?
 
Are your clowns looking ok? What type did you get? I'd do your daily 50% WC on the QT for a couple more days and then move them to the DT. 5.5 gallons isn't very big for a pair of clowns.

Are you taking the water from the DT and putting into the QT for the WC and then adding NSW to the DT?
 
They look ok and are eating fine. They were darting around a little more than usual Sunday night so that's when I did an additional set of tests and found the ammonia spike. They are ocellaris, 1 tank bred and one "unknown" measuring 3/4" & 1 1/4".

DSCN2934.jpg

That's a 2" PVC elbow.

The W/C are done with NSW each time. I make about 25 gallon of RO (5 TDS) each week and mix 5 gallon at a time using IO salt. I use an old IO bucket with 50 watt heater and Koralia 3 power head.
 
I'm just saying that if you're having troubles with the water params in your QT and you have a fishless DT.....why not put them in? I'd rather have my fish in a stable tank than an unstable one.

In a QT tank you can keep the fish isolated and can add any medicines you need without having to worry about hurting live rock, corals and stuff like that.
 
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