If one is gradually adding fish to a brand new, cycled 55 gallon aquarium -- which ones go in first? The smallest or the largest? Or the cheapest? 
New tank - in what order to add fish?
- Thread starter Finzzup
- Start date
What type of fish are you considering?
If you are unsure of a species temperament I/we could help you out there as well.
P.S. Onion girl : well said
If you are unsure of a species temperament I/we could help you out there as well.
P.S. Onion girl : well said
I hate to disagree w/ OG but the waste production capability of the fish is equally if not more important than temprament when doing a non-fishless cycled tank. The idea is to avoid increasing the amount of fish related waste faster than your bacterial colonies can expand to handle it.
For example- if you have a tank with maybe 6-8 small fish such as z danios adding just 2 good sized plecos would push the waste factor up by a great deal. The plecos would be putting out many times the waste the tank is already able handle. On the other hand, adding 6-8 small fish to a tank with the two plecos would not.
In addition, the intitial stocking should be done with fish that have the best chance to survive the initial ammonia and nitrite spikes. That is why corys are not a good first fish even though small.
As your stocking level increases over time, it becomes easier to add fish.
This all said, I fishless cycle well seeded new tanks and also use live plants so I normally fully stock new tanks right away. I have never lost a fish doing this.
For example- if you have a tank with maybe 6-8 small fish such as z danios adding just 2 good sized plecos would push the waste factor up by a great deal. The plecos would be putting out many times the waste the tank is already able handle. On the other hand, adding 6-8 small fish to a tank with the two plecos would not.
In addition, the intitial stocking should be done with fish that have the best chance to survive the initial ammonia and nitrite spikes. That is why corys are not a good first fish even though small.
As your stocking level increases over time, it becomes easier to add fish.
This all said, I fishless cycle well seeded new tanks and also use live plants so I normally fully stock new tanks right away. I have never lost a fish doing this.
twotankamin: you do have some points but orion girl is right here. aggresssion *has* to be the determining factor. either it should be in the beginnning or it will be in the end.......
go read a few posts in cichlids or i will provide references. many, many times i have seen posts about evil fish that will not tolerate *any* tankmates. notably fish like my hemichromis, auratus and even convicts........ and then even bigger fish like midas, jags, green terrors........ the list goes on and on..... yet if you put the (probably) smaller or less aggressive fish in first before whatever swimming attitude problem, the little fish has a chance to survive. on the other hand if you add it after, it becomes a feeder or just a dead fish. even my snakeheads held true to this, they coexisted happily with 3 red-eye tetras, but whenever you added fish after, the added fish were food.
considering i saw no specific fish referenced....... and i am sure this holds true for even the less aggressive, aggressive fish.
go read a few posts in cichlids or i will provide references. many, many times i have seen posts about evil fish that will not tolerate *any* tankmates. notably fish like my hemichromis, auratus and even convicts........ and then even bigger fish like midas, jags, green terrors........ the list goes on and on..... yet if you put the (probably) smaller or less aggressive fish in first before whatever swimming attitude problem, the little fish has a chance to survive. on the other hand if you add it after, it becomes a feeder or just a dead fish. even my snakeheads held true to this, they coexisted happily with 3 red-eye tetras, but whenever you added fish after, the added fish were food.
considering i saw no specific fish referenced....... and i am sure this holds true for even the less aggressive, aggressive fish.