My tank finally cycle, now what?

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eddiegunks

Piranha
MFK Member
Mar 6, 2017
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Tillson NY
OK,

I just got my new 90 gallon tank cycle (fishless cycle) . My dilemma is the addition of fish. I'm not sure if I should continue to dose it with ammonia until I'm ready, or if I should just go out and get a couple of starter fish to keep the tank cycling as it should.

What I'm getting at, is how do I keep the nitrifying bacteria alive? I would hate to have it die off during my acquisition of fish. I also do not want the majority of the colony of bacyeria to die off because there's only one or two small fish in there. Will this happen, could this happen?

The fish I was planning to add or not available locally, I need to drive to the other fish store about an hour away and I'm not prepared to do so in the next couple of days.

I will be picking up a fairly expensive jar in the next few days, but I would hate to add him into a new recycle tank, I think I'm going to add him to and well-established day just so I have no issues. What are your thoughts on that? Is a Cycled tank a a cycled tank? Or should I let it age for a couple weeks longer?

Thx
 
If you say it is cycled and you have tested it and have no ammonia or nitrites and have a reading of nitrate. You should be fine as far as adding fish gradually but keep in mind to still test water periodically to make certain parameters are stable and your filter is handling the bio-load of fish your adding. I would personally add the Jar last.
 
Just keep dosing the tank with ammonia, 4ppm, each day. It should convert all of it into nitrate within 24 hours. The day before you get fish do a 90-100% water change with temperature matched water, and be absolutely sure to use plenty of dechlorinator. Go ahead and dose it with 4ppm ammonia again after that. Test it the next day to be sure the cycle is still strong. If you have good results, go ahead and do a 75-90% water change the same way as the day before. Then, get all of your fish and add them all at once.
 
I apologize just reread your thread you can continue with the ammonia dosing until your cycle is complete or add inexpensive fish that you may possibly lose due to the spike of the ammonia and nitrite level until they stabilize and nitrate is evident.
 
Hello; You seem to already know about the beneficial bacteria (bb) and are asking for confirmation about adding fish.
Here is my take. The bb population is in a dynamic balance with the ammonia producers in a tank. If you have a few small fish in an established (cycled) tank for a few weeks then the bb population will have adjusted to the amount of ammonia available from those fish plus maybe some ammonia from decay of things like excess food bits.
If you add some more small fish one or two at a time then they will make more ammonia as a byproduct of their metabolism. This extra ammonia will make it possible for a larger population of to exist and the bb will reproduce quickly to use up this extra nutrient. It is likely the dynamic balance will be stable very quickly and very little of an ammonia spike will occur very briefly.
However if a lot of small fish are added or a single fish of a large mass then the extra new ammonia is a more significant amount. It may take a bit longer for the bb to reproduce enough get back in balance and you can have a slight ammonia spike. With an established (cycled ) tank there will be bb colonies already in place so the ammonia spike should not last a long time, but likely will be several hours to maybe a day or so.

I think there are ways to help with this ammonia spike. One appears to be a reduction of feeding when a new fish is introduced. This reduces the possible decay of uneaten food and as well should reduce the waste products from the fish as well.

Of course water changes (WC) during the days after adding a lot of fish mass will help by removing some of the extra ammonia and also diluting the remainder.

I also suspect chemical treatments for water such as Prime, Safe, or such may be able to bind up some of the excess ammonia.

I like to have live plants in a tank. Floating plants can be put into tanks. The plants may take up some of the ammonia directly. They also are likely to have some bb on their surfaces.

Good luck
 
Thx sk. That was what i was after. I figure after doing 3ppm i should have. A pretty good bunch of bb built up. I just did not want to let em die with only a couple of small fish. But at the same time i dont wanna kill or injure my big expensive fish.

There in lies the unknown.

Edit to add I have several plants in one nice big sword plant in there.

Thx
 
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hello; You are on the right track. keep adding the liquid ammonia until the time you are ready to add the fish. My guess being that stopping with the liquid ammonia a few hours to no more than a day before adding the fish. This is a guess on my part as I have not done the fishless cycle with liquid ammonia.
Do you know about acclimating fish from a fish shop into a home tank?
 
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Thanks again. Yes I know about acclimating fish to the tank.

I just did not want any of my colony of BB to die because I didn't want to injure any large fish ( with the ammonia spike Or a nitrite spike ) I might add.

We have a few tanks set up and doing well. Our oldest one is almost 2 1/2 years. I'm just trying to get better at this so I have a clearer understanding and I do not injure the fish..... especially since my fish are becoming more expensive. Ha ha ha.
 
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We have a few tanks set up and doing well. Our oldest one is almost 2 1/2 years.

Hello; This is even a better situation. You could have had a very quick "cycled tank" by taking solid material from the older tanks. This is what I have done for many decades. When I start a new tank I grab some solid material from an established tank.
I also keep some extra material in my established tanks. For example I got some foam material to use on a sponge filter. I keep some in the back of my power filters. This way if I need to set up a QT or a new tank I can grab the sponge foam and be ready to go.

Back to your new tank. This is what I likely would do. Stop the liquid ammonia a day before getting the new fish. On the day of adding the new fish I would grab something from an established tank and throw it in the new setup. This can be filter media, décor, substrate, snails, and such. Most any solid surface should have bb colonies on the surface as a biofilm. You can do this and likely avoid any ammonia spike.
The only caution that comes to mind being if there are any potential disease or parasite issues in the established tank. Recent Ick outbreaks even if none currently present or unexplained recent fish deaths in a tank might make it unwise to get material from that tank.

Good luck
 
Thx SK

I know i could have jump started the nee tank with the old tank's filter media, i was jusy trying to let it run without.....for the experience.

I will take your suggestion and add some filter material to the new tank when i add the fish, that is a great idea. Thx.

Yeah, i am battling ick right now (in a different tank from the two we are discussing). I think a clown loach started it! Everytime i have an ick issue it is from those darn CL. No more for me!

Cheerrs

Eddid
 
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