Buying a whole slew of fish at once

[gksipps]

Newbie question... I have not seen anyone else ask this question, and I DID do a search, so as to look less like a twit unworthy of the hobby. Do you have to go through a new cycle every time you add a new fish (like add a fish, wait six weeks, add a fish), or once your tank is cycled, do you just add all your fish at once? Ours is cycled, but I am afraid to purchase more than one fish at a time, and without a long time span between. (Not to mention the little accident our puffer had the other day that I am now spending all my energy trying to console him and nurse him back to health, and do not have any extra energy left for a new little guy.) Your thoughts?

 

[thomas712]

Now that your cycled you need to add one or maybe two if they are small fish, and let the bio load catch up to handle it. Adding many fish at once is a very bad idea IMO. This will cause an overload on the bio load and cause problems.
Thomas

 

[beaslbob]

Originally posted by gksipps
Newbie question... I have not seen anyone else ask this question, and I DID do a search, so as to look less like a twit unworthy of the hobby. Do you have to go through a new cycle every time you add a new fish (like add a fish, wait six weeks, add a fish), or once your tank is cycled, do you just add all your fish at once? Ours is cycled, but I am afraid to purchase more than one fish at a time, and without a long time span between. (Not to mention the little accident our puffer had the other day that I am now spending all my energy trying to console him and nurse him back to health, and do not have any extra energy left for a new little guy.) Your thoughts?
Well basically everytime you add life to your tank you will experience a 'new' cycle. The question is how large of a cycle this will be. Obviously the largest increase in bioload is when you go from nothing to something. Keeping the first something small is important to reduce the time it takes for the tank to adjust. But if you tank already has cycled with 5 fish, then the tank will cycle very quickly when a 6th fish is added. To exaggerate say the tank was already supporting 100 fish. the tank could adjust literally in hours (if not minutes) to the addition of a single additional fish.
One thing to consider is the type of fish being added. For aggressive, territoral fish an old rule of thumb was to add either 1 or 6 but nothing in between. If you only add two, then there is a very good chance one is much stronger than the other. the weaker will probably not make it. With 6 a pecking order can be set up where each individual is much more evenly matched with those in the order around them. But then with marine fish prices we probably only add a fish at a time anyway. Also, 6 yellow tangs (for instance) can not be suported by a 55g anyway.

 

[broomer5]

My thoughts gksipps ...
We use the word "cycle" most often to describe the conditioning period for a brand new tank. As you know, this conditioning period allows for a new tank that contains few if any bacteria, to become a tank that has an established population of bacteria.
Once the tank has the necessary population of bacteria, necessary population to process and convert the "given" amount of ammonia to nitrite, and then the nitrite to nitrate ..... then the tank would be considered "cycled".
This could be called the tank's "initial cycle".
The tank can now handle "some" additional ammonia/nitrite because the bacteria are now present, and they will do what they do.
You never want to add too much food/fish/waste to the tank at this point - because even though it's "cycled" ..... it's in no condition to handle much more wastes.
So if you slowly add a fish at a time, and let the exisiting bacteria population respond to the new wastes .... then you'll be much safer. The bacteria colonies will grow with the added fuel they need. The bacteria colonies will be allowed the time to reproduce and handle the additional ammonia.
The nitrogen cycle is always going on in the tank.
Feed fish
Fish produce wastes containing ammonia
Bacteria consume/convert this ammonia to nitrite
Other bacteria consume/convert the nitrite to nitrate
Nitrate is either eliminated by deep sandbed to nitrogen gas, is taken up by green micro or macro algae, or will continue to build up over time.
This nitrogen cycle is always going on ..... where as the "initial cycle" more accurately describes the conditioning of a new tank to accept fish wastes.
You are wise to fear adding more than one fish at a time to a new tank and not allowing enough time inbetween fish additions.
Wise for sure.
Going slowly, and managing your fish additions, is one of the very best things you can do.
For new folks to the hobby, and for experienced people as well.

 

[saltmarsea]

Be very careful not to jump the gun...I have my specs in the signature...had a 20 gal and I stocked it tooo soon, it is a hazard and a pain inthe neck really to get past the overload! Just be patient ok, ONE or TWO at a time...watch the levels for a week, and then wait to see become stable within the next week....then think of more. It WILL save you time, headache, and MONEY..I ended up losing clowns, coral beauty angel, Blenny becuz I jumped too soon, ended up buying a 10 gal QT tank while I tried to recycle...thank goodness my 2 seahorses made it through! It started as me playing catch up with daily water changes....trying to keep them in the tank, then I said I am poisoning them, I need to move them and I did to allow a cycle. I put in a "dirty" yet clean pad from my sis and added biozyme & cycle to my tank while the stock was out and it went back to zero...don't get too excited to see the tank all set up quick, it won't be worth it to you when you overload! GOODLUCK & Patience is KEY!! I still Only have my 2 seahorses, no other fish....and I am waiting til I perfect everything......almost there...GL MarSea