I messed up by underestimated cycle time

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Spence

Polypterus
MFK Member
Jan 21, 2015
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Long story short I expected a much quicker cycle on my new 5' 120 gallon aquarium. Since it was seeded with established filter media I was expecting a couple days of a cycle rather than weeks. I currently have 2 Severums and a Green Terror in a 29 gallon which is starting to cause some territory issues (mostly between the Severums as neither seem up to challenging the Terror). What I was thinking of doing was moving the smaller of the two to the mid cycle tank to relieve some of the mounting aggression. As you can see I'm stuck with two bad choices (leave them where they are and risk the bullying or move one fish into a poisonous environment.)
Current reading on the tank are:
Ph 7.4
Ammonia: 0
Nitrites: somewhere between 2.0 and 5.0 (estimating it to be closer to 2.0)
Nitrates: 10

Looks like the cycle may be coming to an end based on these readings so what do you all think...ride it out or move one over?
 
I would not put the fish in with 2-5 nitrite. I would probably just ride it out, utilize a divider if need be. Cycle should be coming to an end based on readings. You seeded the new tank with bacteria, but have you been feeding the bacteria with ammonia since there are no fish in the tank?
 
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Yes, I've been dosing it up to 2ppm for ammonia daily. It just started clearing all this overnight (I only test in the morning so it could be working faster). I was thinking of only dosing up to 1ppm to get less nitrites, but I'd prefer a nice strong bacteria colony. If I did move the severum over I'd definitely be doing more water changes to get this lower. But it would surely be living in some pretty crappy conditions between changes (and any resulting swings from the ongoing cycle).
 
I'm also afraid to put in a divider because I'd be reducing the territory even more (splitting the tank in 3 parts would leave almost no room). I'm not sure if that would be worse than the aggression I'm seeing. There hasn't been any real harm done yet, but I'm sure its coming.
 
Here's what I would do:
Stop dosing with ammonia and do nearly a 100% water change. Once the tank gets to the right temp, put all 3 fish into the 120. Move all the filtration system over to the new tank (with original media as is), and all the ornaments/decors from 29gal as well.

After 24hrs, check parameters. If there's ammonia or nitrite do 50% wc. Repeat the next day. If there is an increase in ammonia/nitrite, increase wc to 75%. I'm betting you won't have to do that many wc, if at all.

They'll probably be stressed from the move and new environment, so I would also recommend you leave the tank's light off for about a week, and don't bother trying to feed them for several days.
 
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Here's what I would do:
Stop dosing with ammonia and do nearly a 100% water change. Once the tank gets to the right temp, put all 3 fish into the 120. Move all the filtration system over to the new tank (with original media as is), and all the ornaments/decors from 29gal as well.

After 24hrs, check parameters. If there's ammonia or nitrite do 50% wc. Repeat the next day. If there is an increase in ammonia/nitrite, increase wc to 75%. I'm betting you won't have to do that many wc, if at all.

They'll probably be stressed from the move and new environment, so I would also recommend you leave the tank's light off for about a week, and don't bother trying to feed them for several days.

Suppose I add all the decorations and filter...do you think that would have a big effect without the substrate? I've always thought the bulk of the bacteria was there.

**Also I noticed you are from Southern NH...I used to live in Atkinson for a couple years.
 
Suppose I add all the decorations and filter...do you think that would have a big effect without the substrate? I've always thought the bulk of the bacteria was there.

**Also I noticed you are from Southern NH...I used to live in Atkinson for a couple years.

The substrate does have bb, but not the bulk of it since its O2 poor. This is true, however, if you are using undergravel filtration.

I live in Pelham
 
I moved the filter and most of the decorations and Nitrite dropped to .25 overnight (ammonia held at 0 and Nitrates jumped up to between 30 & 40. Looks like I could just about be there. Going to do a big water change and move
them over.
 
I don't know what you're wc schedule is, but once everything settles, I would just like to recommend, at the very least, a 50% weekly wc..... but the more the better! I do well over 50% every 3-4 days on my 3 tanks.
 
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