Topic: How soon should you do water changes to reduce NitrAte?

[redwoodbsq]

OK, 1st off, it's not my fault.  The situation was dropped on me- the co worker "taking care" of the tank got fired.

55 gallon, nice set up, couple of plants... OVER STOCKED.  (I'm working on this part and the boss)

I tested the water before I started the water change (you know, to know how much to take out).  I was shocked to see our nitrates off the chart.    Makes sense when you consider the over stocked issue and that he wasn't on the ball with the tank.

So I did a 30% water change because my back is just killing me after that much lifting of 8 gallon buckets.  Two days later I went back and tested again, we're still stupid high (which I expected since it was stupid high before).  We went from I'd guess 160 (hard to tell that far red) to a probably 110.  Still lethal.  Fish don't seem too stressed out about it, just stressed about people messing in the tank.  The first water change had nasty amounts of poo from the gravel vacing, second significantly less than I expected considering the still high level of nitrates.  So I think the gravel is pretty clean all things considered.

Here's my question... How many times can I do a 30% water change every other day until I do harm to the bacteria and screw it all up?  I know I have to get the nitrates down ASAP, but don't want to mess it up even worse than what's going on now.  I've just never had to reduce levels this much before, I always stay on top of it at home.

P.S. as for the over stocking, I know it's an issue and if it was my tank I'd take care of it right away, but office politics is not letting this be an option.  I realize that this (and the neglect) is the reason for the sky high nitrates but hands are $^#%@ tied about it right now.  Got to make the best of the situation.  

[wendyjo]

You don't have to vac the gravel itself each time you do a water change.  Most of the bacteria is on the surfaces - tons in the filter, some in the gravel, and some on the decor, etc.  But not all that much in the water column.  So I think you should be fine. 

[ShieldWolf]

Good job stepping in and handling the situation. You can do as much water changes to bring it down to an acceptable level in a short amount of time. As Wendy pointed out, the beneficial bacteria should be fine. Good luck.

[Ppulcher]

In addition to the water changes, you might consider adding some easy, fast growing floating plants like guppy grass (najas species) or hornwort.  They do a really good job of taking up a lot of the nitrates.

[Cholly]

You can do daily 30-50% water changes as long as you dechorinate and match the temperature as close as possible. The bigger the water change, the more critical the temperature match becomes. That's why most people don't recommend really big water changes. If you aren't using an undergravel filter, you can vacuum the gravel every day without harming the cycle, over 90% of the good bacteria resides on your filter media in your filter, it needs good water flow to supply it with food and oxygen.

[redwoodbsq]

Well, an update:

It's taken awhile, but I finally have all of the levels under control!!  

After I had posted, I did a full water test and found the Ammonia OFF THE CHART, pH at the bottom of the scale, and a blip of NitrIte.  NitrIte was the first to go.  Had to change to a different water conditioner since apparently we have STUPID HIGH levels of chlorine in our water.  Ammonia dropped to .25 with consistent water changes but would not drop off completely, but I finally saw 0 today, and yes I did a happy dance in my office.  pH was really worrisome, it would never come off the bottom of the scale, and my Nitrates would flux between 60-100... the overstocking was just killing me, every time they would go down, two days later they'd be right back up to 100.  Gave away one of the giant fish, so it's only stupidly over stocked instead of insanity.  Wearing down the boss on getting rid of a few more.

But with serious amounts of upkeep on the tank, I am pleased to announce: Ammonia 0, Nitrites, 0, Nitrates 40 (yup, getting the buckets now, but at least it's not lethal anymore!), and pH of 6.6.

 

[Guppyguy]

Thank goodness you got it under control ! Nitrates mean water changes, even I know that, but they're SNEAKY!!!  With an aquarium that size, it's hard for me to imagine fluctuations like that! 

[Cholly]

Happy dance time! Way to stick with it!