Need Help Getting Nitrates Down

[CalmedByFish]

My 55 gallon hadn't gotten a single water change in years. The Nitrate level was somewhere well above 80. After nearly emptying it by gravel-vacuuming, and refilling it with new water reading 0 ppm Nitrate, the tank was immediately near 30 ppm Nitrate. I then put so much pothos on the top that the roots fill about half the tank, and added 2 Seachem resin bags to the HOB filter. 

Just over a week later, Nitrates were back up to 40-80. It's now been a month since that 95% water change, and Nitrates are still 40-80. 

There's no way it's overstocked or overfed - it's just an angelfish, and Malaysian trumpet snails. I've been very careful to give the angel just a flake more than he'll eat per day, letting that little bit fall down for the snails. Ammonia and Nitrite are always at 0.

So now I'm looking at a bottle of bacteria that contains a "blend of aerobic, anaerobic, and facultative bacteria which facilitate the breakdown of waste organics, ammonia, nitrite, and nitrate." But I don't know of a place in my tank that's low-flow enough for the denitrifying anaerobic bacteria to live. (Underneath the gravel maybe?)

My only other thought is to try to stuff the tank with Vallisneria, which I hear is great for gobbling up Nitrates. 

Based on your experience, what would you try? 

[Daniel]

As you mentioned, it is hard to keep a tank full of live plants and also a have a nitrate problem. Hornwort has good reputation for gobbling up nitrates. But if you like Vallisneria, I would give that a try first.

[CalmedByFish]

1 minute ago, Daniel said:

As you mentioned, it is hard to keep a tank full of live plants and also a have a nitrate problem. Hornwort has good reputation for gobbling up nitrates. But if you like Vallisneria, I would give that a try first.

I actually just ordered a bit of hornwort a few days ago! Not here yet, but that tank can be its first home! (The long-term plan is a very simple little pond this summer.)

Sounds like you think I have a better chance at success with plants than with the bottled bacteria? 

[Daniel]

Just now, CalmedByFish said:

I actually just ordered a bit of hornwort a few days ago! Not here yet, but that tank can be its first home! (The long-term plan is a very simple little pond this summer.)

Sounds like you think I have a better chance at success with plants than with the bottled bacteria? 

I do. Plant themselves are steady consumers of nitrates and as a bonus provide wonderful substrate for beneficial bacteria and additional carbohydrates and oxygen that beneficial bacteria need. It is hard to go wrong with plants.

[darkG]

It is intriguing. If your bacteria are super-efficient, there will be shortage of ammonia so the plants need to go for nitrates. If the bacteria are meh, the build-up of nitrate would be modest.

I too believe hornwort is well worth a try. You can just leave it floating until further notice, 

[CalmedByFish]

Gosh I love nerds. 😂

Alright, I'll forego the bacteria for now, and try the hornwort that's on the way. It should arrive within a few days. 

And as a Plan B in case the hornwort arrives looking pathetic, I'll hit up the Co-Op for a load of vallisneria. 

Thanks guys!

[Ben_RF]

The crazy nutrient suckers that Pothos are really doesn't start occurring until they have established a good aquatic root base system in the tank and new leaves are beginning to sprout.  This may take a few weeks for them to ramp up. 

[Trish]

Would you be dealing with Old Tank Syndrome if you don't do regular water changes even with plants ?  

[Colu]

2 minutes ago, Trish said:

Would you be dealing with Old Tank Syndrome if you don't do regular water changes even with plants ?  

I agree with @Trish