When Is A Tank Cycled? (without Fish)

[tlef316]

Hey guys. Long story short, i tried to fishless cycle my first tank and failed. I was able to produce enough bacteria to get rid of amonia, but the nitrite wouldnt drop. Eventually, the ph crashed below 6 three times and i gave up. I talked to an online friend of mine, who said i could just drain the tank, refill it and add fish, so thats what i did. I tried to fishless cycled for 3.5 weeks, but i am starting a new career, and wanted to get some fish in there before i did.

75 gallon freshwater tank. Sand substrate, artificial plants, mopani wood and some rock formations. pic

last saturday (june 9th here in the US) i added fish. 10 danios (7 golden zebra, 3 leopard) and 7 peppered cories (2 got sucked onto the filter tube and died, but the others are doing very well)

Since day 2, my tank has been 100% free of amonia and nitrite (i tested twice a day for the first 5 days, once a day since) Nitrate has held steady between 10 and 20. (using the API liquid test kit) Ph has hovered between 7 and 7.4.

My question is, when am i cycled? I plan on adding a few more fish this weekend, but i would like to know what would constitute a cycled tank at this point. I would assume no amonia or nitrite for 10 days is a good start, but id like to know for sure. I only ask, because i would like to add some more fragile fish at some point (cardinal tetras, Rams, Maybe clown loaches) and dont want to do so until my tank is mature. Obviously, a tank cant be mature until a few months after it is considered cycled, thus my problem. I cant just have danios and the like forever.

Any help would be greatly appreciated.


pic of 2 of my corys

 

[rdd1952]

Your tank is cycled when ammonia and nitrite are always zero. And even at that, it is only cycled for the fish it has in it. If you add more fish, the bacteria have to multiply to catch up. Don't add any more fish until the tank goes at least 1 week and preferably 2 with no ammonia and nitrite. At that point you can add more but not too many. At most you want to double the bio-load. That way the bacteria can double itself in about 24 to 30 hours and prevent any mini cycle. Then wait a week or 2 more before adding more fish.

Most likely the corys that ctuck to the filter were either sick when you got them or were injured when they netted them. Every time I buy corys, it seems they injure one with the net to the point that it dies. A healthy fish will never get stuck to the filter.

You're right about the mature tank. You can most likely add the cardinals. They are generally considered more hardy than neons. As long as the ammonia and nitrite stay at zero, you won't have any problems with them. The advantage you have with a mature tank is that it is less likely to be hit by a major disaster.

BTW, I love peppered corys but never had any luck with them. Everytime I bought them they ended up dying. Never had that problem with any other fish except otos (but they are notorious for sudden deaths).

 

[tlef316]

yeah, thats about what i thought. As of tonight, im going on 11 days without any amonia or nitrite. I think i will add more fish on saturday. Thanks for the heads up on the cardinals. I will definetly be getting a school of them (probably eight)

Would it be better to wait on picking up 3 juvenile clown loaches? I know they are very sensitive to ich, and i dont have a quarantine tank yet.

the cories are great, and seem to be doing well. 2 of them are a little smaller and lighter in color, but they seem to be doing fine. They all hang out together under that piece of wood in the back left, and they love swiming back and forth across the front of the tank (in the filter output current) Seems like they have all gotten slightly bigger too. Im feading them brine shrimp pellets and some flake. (plus whatever they are finding in the sand)

 

[rdd1952]

I've never had clowns before so I'm not sure. If you don't have a Q-tank and don't plan on getting one, you may want to get them now before you get anything else so you have the least amount of fish possible in the tank that could become infected it they do bring something in. When you're in the fish store, find another customer that you can ask whether the store has good healthy fish or not. If it's someone that's been in the hobby a while they can probably tell you the best place to get fish that are disease-free.