my tank has already cylced, nitrates and ammonia 0. i added two more angel fish and an algae eater over the weekend, and turned off my uv filtration for the weekend. my ammonia level is now 2.5. is this okay?
Any ammonia is bad ammonia. .25 and .5 are stressful on fish and 1.0 and higher are extremely dangerous for fish. I would do a partial water change asap to lower those levels. And please read about the nitrogen cycle if you haven't already then you can better understand what is going on in your tank chemically
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What fish were in the tank prior to adding the new fish?
People have this idea that a tank being "cycled" is some sort of absolute thing. An absolute guarantee that any and all ammonia will be immediately handled, so it should read zero at all times, even after adding more fish.
I kind of hate the term "cycled" in this context. I think it's misleading and fosters an incorrect mental image of what's really going on.
What really happens is that colonies of beneficial bacteria grow on various surfaces in the aquarium, and mostly in our filters, especially on our "bio media". The bacteria colonies are just like colonies of any other living things. The population depends on the available food supply.
So if we start off with no bacteria, and then we add some source of ammonia (like fish, or dosing periodically with raw ammonia) the bacteria will multiply until their numbers match the rate of ammonia production in the tank (or the rate at which we add raw ammonia). We end up with just enough (but no more) bacteria to eat the available ammonia. If any more bacteria try to develop, they starve. If there isn't enough bacteria, then we start measuring higher levels of ammonia for a while until more bacteria can arise due to the reproduction of the bacteria.
What you may be seeing is simply a small spike of measurable ammonia because your bacteria colonies are taking a while to "catch up" with the newly added ammonia production from the new fish.
None of this happens instantly. It may take a few days to a week for the populations of bacteria in your system to multiply and increase to match the new level of ammonia production due to the new fish.
I'd like to know what fish you already had in the tank before the recent additions. If it wasn't much, then the bacteria colonies may have been very small, and have a lot of catching up to do. If you had NO fish at all yet, then you may have had almost no bacteria, and may be facing getting things started from scratch at this point.