Why is Adding Multiple Fish at the Same Time Always Discouraged?

[woody189]

I was wondering why it's always advised to add fish one at a time. I understand that the tank needs some time to allow more beneficial bacteria to grow to accommodate the increase in ammonia, blah blah blah, but why can't we add 2/3 fish?
People are always adding pairs of clowns, or schools of 3/5/7 chromis/anthias/firefish at once and nobody seems to advise against it. How is it any different to add a royal gramma at the same time we add a 6-line wrasse and a clown?
I should note that I do realize that certain things need to be added in a certain order to allow the more docile creatures to be established.
People always say wait 2-3 weeks between additions and I don't get why.
The reason I thought of this is because I met some guy that will sell fish at buy one get one 1/2 off, so I would like to take advantage of his policy. Fish are already reasonably priced, and look well taken care of.
Thanks

 

[reefkprz]

you pretty much answered your question with your first line, to allow bacterial growth to catch up to the bioload.
as for is it any different adding say a six line and a clown or two cromis at the same time, IMO its the same, of course some species of fish are dirtier than others so you have to take that into account, depending pon the size of the tank, the imjpact of multiple fish on a 20g will be alot more severe than the impact of the same fish on a 125g. there is a lot of different factors and no one answer fits all situations, but generally it is best to err on the side of caution adding as little change to the bio load as possible at a time.
when adding more than one fish you have to be slightly more aware of the possibilities of spikes etc, and plan accordingly, as well as feed accordingly.
in the end it is definitely possible to add more then one fish species at a time, it is generally best though to make as few changes at a time as possible.

 

[woody189]

Quote:
Originally Posted by reefkprZ http:///t/392156/why-is-adding-multiple-fish-at-the-same-time-always-discouraged#post_3480668
you pretty much answered your question with your first line, to allow bacterial growth to catch up to the bioload.
as for is it any different adding say a six line and a clown or two cromis at the same time, IMO its the same, of course some species of fish are dirtier than others so you have to take that into account, depending pon the size of the tank, the imjpact of multiple fish on a 20g will be alot more severe than the impact of the same fish on a 125g. there is a lot of different factors and no one answer fits all situations, but generally it is best to err on the side of caution adding as little change to the bio load as possible at a time.
when adding more than one fish you have to be slightly more aware of the possibilities of spikes etc, and plan accordingly, as well as feed accordingly.
in the end it is definitely possible to add more then one fish species at a time, it is generally best though to make as few changes at a time as possible.
Gotcha. That's what I figured, but I was surprised that it's never mentioned that someone can get away with adding multiple (different) fish at the same time. Particularly in a larger system.
I have only a purple FF in a 46 gal right now. My next 2 fish will probably be 2 clowns, so I'm going to wait a few weeks, but I'm fairly certain I will be adding a maximum of 2 different fish at once in the future.
Thanks.

 

[geoj]

I would like to add that you don't know when your tanks bio-load is max out, till you add one too many fish. So then comes the question will you take the fish back or add to the filtration. :laughing: filtration...

 

[woody189]

haha. definitely filtration. the only way my fish leave my tank is in a bodybag

 

[deejeff442]

i have added 5-6 fish at a time when i had my 150 gallon. i just fed the same amount for a couple weeks .then started bumping up the amount .didnt have a problem.but also my tank was running for years.smaller tanks like 55 or smaller yes one at a time.

 

[btldreef]

Quote:
Originally Posted by deejeff442 http:///t/392156/why-is-adding-multiple-fish-at-the-same-time-always-discouraged#post_3480881
i have added 5-6 fish at a time when i had my 150 gallon. i just fed the same amount for a couple weeks .then started bumping up the amount .didnt have a problem.but also my tank was running for years.smaller tanks like 55 or smaller yes one at a time.
I agree. In my 155 and my 180 I've added multiple fish at once, but in my smaller systems I try to limit to one, two max.
It's not "necessary" per say to only add one at a time, but it does make it much easier to monitor if it's only one at a time.

 

[geridoc]

While I have a 220 gal system, and could easily add multiple fish with no problem there, I am limited by my quarantine tank, which is a 20 gallon long. So,,,multiples only of small fish are for me. Otherwise, one at a time in the quarantine.

 

[woody189]

Ok. Thanks everyone.
I'll add them one at a time unless I order get them buy one get 1/2 off. And I'll be sure to monitor regularly.