Think I Got Myself Into Some Trouble

[Midas]

Hello,
 
I moved 6 days ago and started my tank over fresh thinking I could cycle it quickly using some cycle stuff and a filter that needs the media changed.  I have South American cichlids in a 125 gallon tank with plenty of air, filtration and a bare bottom.  The fish went in on day two and are healthy but are fighting quite a bit.  I did a water test today and was shocked to see the ph went from 7.0 to 6.0.  Ammonia is about 0.25.  Nitrite is 0 and Nitrate is about 100.  Temperature is steady at 78 degrees.
 
The 6.0 ph level is very concerning and I am not sure if I should do a water change or not.  I have read that you shouldn't change the water when cycling.  I read the cycle info on this site, but I had to put the fish in or they would have died in the cold water in the buckets they were in.  I suppose I could have done things better but this is the situation I am in now, any help would be appreciated.
 
Midas
 

 

[tunagirll]

It's fine to change the water while cycling with fish in, in fact it's something you should do to help keep your fish comfortable. The bacterial colonies are growing on your filter media etc, not in the water

 

[daizeUK]

Hi there Midas!
 
Which 'cycle stuff' did you use?
Did you use any old media with the filter?
How many fish are in the tank?
What is the nitrate content of your tap water?
 
Your nitrates are extremely high and this could be responsible for the pH crash in your tank.  I would do a 50% water change immediately to get those nitrates down.

 

[Midas]

Thanks for the quick responses, I am not sure what type of cycle stuff I used, I threw out the bottle and can't seem to find it online anywhere.  It was made to help cycle the tank and I followed the directions carefully.  I used old media yes with ammonia remover and carbon.  I have a Hagen FX5 so there was quite a bit in there.  There are 6 fish in the tank. A couple are quite big at about 9 inches or so.  I will try and get some pictures uploaded.  There are little to no nitrates in the tap water, which has a 7.0 ph. 
 
I am in process of doing the 50% water change right now.  Media is old, think I should change it or is that helpful with the beneficial bacteria?

 

[daizeUK]

The media is helpful as it is the most likely place for bacteria to live.  I'm a bit confused about where all those nitrates have come from, that's extraordinarily high after 6 days with 6 fish in the tank.

 

[Quigs]

I would say keep the old media in the filter which hopefully still has living bactetia on it, was the media allowed to dry out or out of water for long?

 

[Midas]

The media did not dry out and was back up and running within 24 hours.  So I imagine the nitrates came along with it.  Got the water drained so just gotta refill it now.  Will do another test once that's done.  Thanks again, your answers are very helpful!

 

[eaglesaquarium]

The nitrates are that high because your bacteria are still almost fully functional.  The concern I have is that you still have 0.25ppm ammonia showing with mature media.  Your tank may be overstocked and/or you may be overfeeding.
 
 
At the pH level of 6.0, the ammonia is not a major concern, except for the fact that it is there at all.  It may be a false reading, it may not be.  Nitrates that high after such a short time indicate to me that your tank is most likely overstocked.  That may not be a major issue, except that you need to do more frequent and larger volume water changes.
 
 
But, without a proper stocking list, its hard to say.  I know its hard to believe that 6 fish could overstock a 125 gallon tank, but depending on the fish, it could be, especially since you mentioned that you have some 9 inch fish.  The aggression is another possible sign.  
 
 
 
What's the decor in the tank?  breaking up sight lines will help with the aggression as well, as each fish could claim a bit of territory.  The concern is that fish of that size take a considerable territory.

 

[Midas]

Here's a picture of some of the guys during the water change. One Texan cichlid, one pleco and a mut.

 

[Midas]

After a 50% water change I have this:
 
PH 6.4
Ammonia 0.1 (just a slight tint to the yellow)
Nitrite 0
Nitrate 80? (dark red but not as dark as the other day)
 
Here is a full list of the fish
 
1 Red Midas Cichlid male (about 9-10 inches)
1 Texan Cichlid male (about 9 inches)
1 Pleco
3 cross breeds (Midas and Texan)  1 male and 2 females
 
You might notice in the picture with the big Midas there is a female in the net.  I put her in there while I did the water change cause she is getting so aggressive, she draws blood when I put my hand in the tank.  She continues to attack the fish in the first picture.  They all got along before I moved but she is on a vengeance and killed her sister and mother in the bucket during the move.  I am certain if I don't separate her, she will kill the big mutt (three times her size).
 
I went with a bare bottom to help keep the tank clean so I have been cleaning up the excess food and crap just about daily. 

 

[eaglesaquarium]

I am far from a cichlid expert... but there needs to be some sort of decor in the tank to allow the territories to be clearly defined. 
 
 
In addition, I'd suggest that you continue to change the water until the nitrates are down to about 40ppm - so another 50% should do it nicely.  You could wait and do it tomorrow.
 
 
As far as the aggression of the female, I can't help you with that.  Territories would help, but might not be sufficient if she is a rogue fish.  Do you have a way to separate her other than the net?

 

[Midas]

I tried setting up a big net to split the tank in half, but they tore that down within an hour or two.  I think I might be forced to get the bucket out and find her a new home.  I suppose I will try to put more plants in first.  I had a lot in before we moved and they did not fight.

 

[eaglesaquarium]

That's kind of what I figured... because they had clearly defined territories.