Nitrites are driving me nuts

[fishnewbie]

Hey everyone, I need some help. I'm trying to cycle my tank which I've had for a bit over a month.It's a planted 20Gal, with a gourami,two angels, 6 guppies, 3platties, 2 tetras and 1 rubber mouth pleco. 
so far my ammonia and nitrate parameters have been good ( 0 for ammonia, highest I've ever had on nitrates is 40) , but my nitrites are driving me crazy. they are consistently above 0.5, 1.0, and sometimes even 2.0. The only way to reduce them is to either add prime or do a water change, and even that is not a permanent solution. my nitrates do increase  a bit between days which drives me to think some of the nitrites are becoming nitrates, but I don't understand why they won't drop closer to 0. I've been having this problem for about two weeks now. I did a 30%, then 25 % water change three days later, but my nitrites were still closer to 2.I did a 75% water change3 days aga which dropped my nitrites closer to 0.5, but they are climbing back again closer to 1. 
What would you guys recommend ? I've been adding stability , pristine and prime daily for 9 days but it doesn't seem to be working.

Through all of this the fish are acting fine, I haven't noticed any behavior except for nibbling on the plants, mostly because I haven't fed them for 5 days now ( advice from my local fish store to help combat the nitrites) .

PS: my tap water shows 0 nitrites. 

[fishnewbie]

I actualy haven't replaced the cartridge, only the sponge thing that's supposed to reduce the ammonia at the front of the aquarium that's supposed to be replaced every three weeks ( it turned black and looked pretty messy) otherwise I added seachem bio-matrix inside the filter to add more habitat for the bacteria and don't plan on changing the filter cartridge until my cycle is complete.

[DaveSamsell]

@fishnewbie, To increase surface area, a coarse, pre-filter sponge would be beneficial on the filter intake.  

Here is an interesting article to read:

https://www.aquariumcoop.com/blogs/faqs/which-pre-filter-sponge-should-i-get

[Levi_Aquatics]

I would suggest adding a pre-filter sponge and or a sponge filter as this helps give the bacteria that turn the nitrites into nitrates a place to multiply. You might also want to add some more live plants to help you with the nitrates when the bacteria starts doing its job. I hope this helps!

Edited February 10, 2021 by Levi_Aquatics

[Kirsten]

Yeah, more sponge filter media, live plants, and patience. The bacteria that convert nitrite to nitrate are a little slower and longer to get started than the ammonia eaters. I've found that precanned cultures like API Quick Start, Stress Zyme, Seachem Stability, or those little aqueon pure beads all help those awkward first couple months.

[David Ellsworth]

You've had the tank set up for a little over a month? That maybe a lot of fish all at once for a relatively new tank and one of them a pleco. I think you may have added too many larger fish all at once (gourami, angel fish, platties, pleco). The pleco produces a lot of waste and needs lots of food, furthermore, he may outgrow the 20 gal eventually (they can get up to 7 inches I believe). Those angel fish are likely going to get too big for a community 20 gal as well. I bet they are fine now, being small, but many people keep them in 55 gal tanks or larger because they can get large.

 

I would increase the frequency and amount of your weekly water changes. maybe 25% to 30% two times a week or so and see how that helps. You may have to adjust this more. Your tank will likely adjust to the load, but keep an eye on the pleco and angel fish. As many of these fish get bigger they may work in your tank, but you will need to increase your water changes and maintenance accordingly. 

[JaredL]

Perhaps your Seachem Stability or Pristine is causing increased nitrites? If you are getting nitrates and 0 ammonia then you should have the proper bacteria for a "cycled" tank established. I think it's possible the "bacteria" cultures you are adding in the tank may be throwing your balance out of whack. My suggestion would be to do a good water change using only Prime conditioner and see how that works. Keep track of your nitrites and do more water changes as need to keep them low, but only add Prime. If I'm right, I would expect to see results within a week.

Edited February 11, 2021 by JaredL

[Mmiller2001]

Double your filtration and dose prime, heavy, every day till it finally cycles.