Cycling Large Tank W/small Fish

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MomeWrath

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OK Don't shoot me for asking this please...
I'm setting up my 75 gallon tank with the intent of housing one single oscar and nothing else. It will have a wall to wall Poret foam mattenfilter on one end, with a 400 GPH pump. I have a piece of poret currently marinating in another tank's filter, to get some BB established. I'll use that along with some existing plants from another tank (which will live behind the filter wall, away from the fish, facing a bright window) and plan on swishing of other filter media to seed the filter wall.
All that being done, and of course with light feeding, Aqua Vitro Seed, Prime, and heavy water changes and the intent of buying a very small oscar... I feel like I should be ok to go on and put him in there. It seems like 75 gallons ought to be enough to dilute the ammonia while the biofilter catches up, since I'm not starting completely from scratch and the available surface area of the filter is enormous.
Am I nuts? I mean, how bad can a 2" fish poison 75 gallons of water?
 
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GrayRas

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You are not nuts at all, I say go for it. I cycled my 40 gallon tank from scratch starting with 3 fish as a method. So I'm sure one will do fine in a 75 gallon especially since you’re starting with some BB.. Why are you only intending to have just one in the tank? Permanently or to start?
 
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Meghanfloof

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Magicpenny75 said:
OK Don't shoot me for asking this please...
I'm setting up my 75 gallon tank with the intent of housing one single oscar and nothing else. It will have a wall to wall Poret foam mattenfilter on one end, with a 400 GPH pump. I have a piece of poret currently marinating in another tank's filter, to get some BB established. I'll use that along with some existing plants from another tank (which will live behind the filter wall, away from the fish, facing a bright window) and plan on swishing of other filter media to seed the filter wall.
All that being done, and of course with light feeding, Aqua Vitro Seed, Prime, and heavy water changes and the intent of buying a very small oscar... I feel like I should be ok to go on and put him in there. It seems like 75 gallons ought to be enough to dilute the ammonia while the biofilter catches up, since I'm not starting completely from scratch and the available surface area of the filter is enormous.
Am I nuts? I mean, how bad can a 2" fish poison 75 gallons of water?
Sounds good to me, except I would still add some seachem stability or something to make sure the ammonia doesn't shoot too high!
 
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Hunter1

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Your plan should work. How long are you leaving the porter in the cycled tank?

I’ve cycled many tanks with an air driven sponge filter that was in a cycled tank for only a month.
 
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Zigi Zig

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Hello
You can put starter fish such as minnows for bait from local bait store is cheap. I wouldn't put any other fish in tank until you will complete the cycle once you do you can release minnows to any ponds or rivers as they were catch there at first place...
 
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GrayRas

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The only thing I would consider is that your beneficial bacteria need to be fed as well. If you are starting with all of this BB already you could potentially starve and kill some of the bacteria by only having one oscar. There won't be enough bio waste ammonia to support the colony if it is already sizable. I would recommend maybe 2 oscars and 3-5 cherry barbs or rummynose tetra or sumn of the sort. You have lots of volume in a 75gal so I'm sure they will be ok as your tank cycles and you will have more ammonia bein produced to feed the BB, which in turn gets your nitrifying bacteria goin etc.. Better cycle I would argue
 
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Meghanfloof

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GrayRas said:
The only thing I would consider is that your beneficial bacteria need to be fed as well. If you are starting with all of this BB already you could potentially starve and kill some of the bacteria by only having one oscar. There won't be enough bio waste ammonia to support the colony if it is already sizable. I would recommend maybe 2 oscars and 3-5 cherry barbs or rummynose tetra or sumn of the sort. You have lots of volume in a 75gal so I'm sure they will be ok as your tank cycles and you will have more ammonia bein produced to feed the BB, which in turn gets your nitrifying bacteria goin etc.. Better cycle I would argue
oscars need quite a bit of room. Personally I wouldn't put two in, but that might justt be me
 
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MomeWrath

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Yeah I'm actually feeling a teeny bit guilty about keeping even one oscar in a 75. I won't add more than that. I don't want to build up this huge colony for only one fish, and my thinking is that as he grows, the BB colony will grow with him accordingly. He will be our "wet pet" since we can't have a dog. My husband is excited to feed him lol.
I've had the poret block in the cycled tank for a week, and it'll be in there at least another week. My filter materials don't arrive until tomorrow, then I have to set it up and do all the gravel/rocks/fill the thing up etc... Between my daughters extracurriculars and life in general that won't happen until this weekend. I have three running tanks that I was going to squeeze their poret filter blocks into this tank and then go get the fish. That's the plan anyway. Get the fish in there before the die-off starts.
I love Poret foam, in case anyone is curious. Been running Freshwater off if it for eight years and I'll never go back.
 
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AquaticJ

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Squeezing filter media won’t do much, I would take a little bit of media from each established tank and put it in the new filter. I haven’t cycled a tank in a long time, I have 12 tanks. All I do is take some bio media from establised tanks and then add fish, never get ammonia or nitrite spikes.

Wouldn’t even worry about any BB dieoff because they’ll die off to match the bioload, and as the Oscar grows they’ll grow.
 
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