Nitrates in Oscar Tank - I'm pulling my hair out!!!

[Myka]

It's a 55 gallon tank with a three year old 9" or so Tiger Oscar, and a 7" Common Pleco. Waterchanges are about 25% once a week. Filtration is provided by an AquaClear 500, and an AquaClear 200. Filter media (just filter floss) is rinsed at waterchanges, and replaced a few times per year. There's an AquaClear powerhead in there for circulation too, I think it is about 300 gph. 2" of natural gravel that averages about 1/4" diameter. Gravel is vacuumed profusely during waterchanges. There's a few lava rocks in there too. The Oscar has had hole-in-the-head for years...is that from poor water quality?

Temp ~ 74-76
Am ~ 0
Ni ~ Trace
Na ~ 75 ppm

 

[richiestang_78]

Well I always replace my filter floss once a moth and never bother rinsing it off since I just use it for the mechanical aspect. What is you nitrates usually at?

 

[zenkatydid]

i think your filtration is not up to speed. you'd have much better results with a cannister on that size of tank, with that high bioload. i assume you are rinsing the media in tank water, not tap water, right? but even so, it's just not enough area for bacteria to live on for that tank, imo.

 

[JDogg]

It's a 55 gallon tank with a three year old 9" or so Tiger Oscar, and a 7" Common Pleco. Waterchanges are about 25% once a week. Filtration is provided by an AquaClear 500, and an AquaClear 200. Filter media (just filter floss) is rinsed at waterchanges, and replaced a few times per year. There's an AquaClear powerhead in there for circulation too, I think it is about 300 gph. 2" of natural gravel that averages about 1/4" diameter. Gravel is vacuumed profusely during waterchanges. There's a few lava rocks in there too. The Oscar has had hole-in-the-head for years...is that from poor water quality?

Temp ~ 74-76
Am ~ 0
Ni ~ Trace
Na ~ 75 ppm

you should not have ANY nitrite.... do a good 75% water change ASAP. but DO NOT vac the gravel or change the filter floss at this time. most likely are cleaning to much all at once. each week just vac 1/2 the tank and only change the filter floss in ONE of the filters in any week (unless you are getting alot of crap building up i do not change my filter floss more then once a month... you are removing to much of the beneficial bacteria at each cleaning...

 

[Myka]

It's actually my mom's tank. I don't think she's tested it before, so I tested it for her to show her how bad I knew it would be. I think she rinses the filter media in tap water. I was suspicious about why there was any Nitrites. Even if there IS enough filter media for the bacteria, that wouldn't make the Nitrates go away. As far as I know (aside from expensive equipment) to make Nitrates go away is waterchanges or LOTS of live plants...? Is there something I don't know about? Tap water tests 0.5 nitrates for any interested people.

 

[Fishyfanatic]

Increase the water changes to 50% per week. For the next several days I would perform 50% every day to get the level down. Then just maintain it with 50% per week.

 

[Mosaic]

PWC and live plants are pretty much the extent of your options. You can bump your water changes way up. Hornwort or some small floating plants would probably be the only plants you could keep if you wanted to try some, since both of those fish will be determined to uproot anything planted.
The hole in the head is from your water quality, yes. It is irreversible, but you can prevent it from getting worse by bringing your nitrates down and ammonia and nitrites at 0.