Overkill or not ? Bacteria Bloom!


Feeder Fish
MFK Member
Feb 15, 2017
Ft. Lauderdale
So I got my new tank, 55 gallon.
Got 2 new filters for it.. 2 canisters, cascade 1000's
1 without filter media, (only bio balls) in every slot 25.
second with filter pads, sponges, etc. etc.

Prepped all rocks, for the tank..
Put them in a tub with Baking soda for 3 days,
after that 2 days hydro-peroxide
1 day clean water after that,
Then 45 minutes in the oven at 385f.

So I know those were bacteria free.. etc. etc.
and ready to go..
not my first rodeo..

put some pieces of driftwood to stabilize the PH..
etc. etc. all the stuff done..
got all running..
Worked nice for 20 days...

Now I feel that I over-killed on the filters, because the first thing that happened after the second day is bacteria bloom.. and like normal I wait and wait.. and be patience for good bacteria to set in.

its still cloudy like hell (not green) so its not algae bloom
and my nitrate is out the roof..
its over 80ppm,
i tried chemicals to kill it..
it went down between 5 and 10 for like an hour and spiked up again and fast.

here's the funny part, nitrite is good ( just the N03 )
never seen this happen in any of my tanks, so I'm muffled.
Ammonia is (non existent, it would not even read)
And PH = 6.3
Wonder why N03 is that high, because there's no fish in it yet..

any advise or answers on whats causing N03 to spike are appreciated and very welcome,
on the why I have bacteria bloom and if its just because I'm over-killing on the filters.

Let me rephrase ( 0 fish in it )
- National Geographic Aquarium Sand
- 2 Pieces of Malaysian Drift-wood
- 5 Rocks (prepped as mentioned above) ( done that process over a 100 times, never had issues )

Any answer/advise will be appreciated..

PS. I did consider plugging a UV-sterilizer on it for a few days, but i rather get some input on what it might be from others first..

Thank you,

Fish Tank Travis

Redtail Catfish
MFK Member
Feb 28, 2016
Dayton, OH
Are you doing a fishless cycle with pure ammonia?

I'm a bit lost on what you're describing because nitrates don't spike, then go back down, then spike again. Nitrates are the end result of the nitrifying bacteria cycle, and can only be removed by doing water changes. Also, without fish, the only way to have a nitrifying cycle that produces nitrates would be to use pure ammonia.

As far as a new tank being cloudy, I don't think that's very uncommon. I went through the same thing when I set up my 220.


Feeder Fish
MFK Member
Feb 15, 2017
Ft. Lauderdale
i used a fizz tablet to see if it would kill the nitrate.
it did.
then when that stopped working.
it was back up
Ammonia = like none existing..
what makes it weird.
even brought water sample to pet-supermarket and a independent store to make sure i wasn't crazy.

and I've dealt with cloudiness before, it never stays for over 2 weeks tho.
now its up to 20+ days.

Fat Homer

Mmmmm... Doughnuts
Staff member
MFK Member
Mar 16, 2009
I guess the question is, since its a fishless cycle, you have to be feeding the tank something to help the cycle going...

Or have you literally just got water + wood + rocks and those fizzer tabs???

If its just what i mentioned, how are you preparing the tank for fish???


MFK Moderators
Staff member
MFK Member
Jun 7, 2007
Isla Taboga Panama via Milwaukee
I just googled the Ft Lauderdale water quality report to help with the mystery.
Chloramine (average 2.4ppm) is used in the city water supply as a disinfectant, so ammonia is used (normally 4parts chlorine 1 part ammonia) to create chloramine so there will be a slight ammonia bump to help create or feed nitrate producers just sitting fish less.
Nitrate from the tap is < 1.0 ppm so the tap water is "not" the cause of 80ppm nitrates.
But to me nearly all newly set up tanks go thru some sort of a bacterial bloom, so to me not a big deal just need a little patience. Some last a few days, some a month or more.
Especially with drift wood added, this may contribute to the bloom (and/or)discoloration of the water. Wood may have dead critters inside which could cause a bloom and a spike.
If the wood has not been previous soaked, tannins will leach out, some wood leaches yellow, some brown, some dingy grey.
Also messing with the chemistry (fizz tabs etc) may contribute to exacerbating the problem, by not allowing the normal cycle to reach equilibrium. Daily partial water changes would be much more useful, and because beneficial bactera are sessile, there is no worry about reducing the population.
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MFK Member
Sep 8, 2014
do water changes. Solves the nitrate and cloudiness issue. Using chemicals to remove nitrates is never a good idea in my book.