Zero nitrate - High Phosphate

mues · Dec 6, 2023

I know this has been posted many times on here before, but curious as to any plan I should take.

My testing today shows .7 phosphates and 0 nitrates (Hanna)

The tank is a new tank, and as such is entering what I thought would be the ugly phase. Getting some brown algae growth which was expected.

My question is.... do I bother putting a reactor in place, or just let it run its course? The fish seem unbothered, however I do have some soft corals coming in next week and am slightly concerned about that. Zoas, GSP, Xenia.

All other parameters seem to be fairly stable, I know I had nitrates at around 2ppm about a week ago, not necessarily worried about that drop, more so the phosphates.

I am running a skimmer 24/7 and having to clean it about once every 5-6 days.

mues · Dec 6, 2023

Anyone before I go out and blow money on a reactor?

rhitee93 · Dec 6, 2023

A couple of us are in a similar situation and have been hashing it out in real time in this thread:

https://www.reef2reef.com/threads/over-1-year-in-and-still-having-parameter-issues.1020322/

The TLDR version for my situation is that about the same time my nitrates finally hit zero, I started getting a brown slime on everything. I dosed nitrates slowly for several days, and got my level back up to 10ppm and the brown slime has pretty much receded.

EricR · Dec 6, 2023

How new is new (tank)?
Personally, I think I'd be more worried about 0 nitrates if that doesn't come up.

mues · Dec 6, 2023

EricR said:
How new is new (tank)?
Personally, I think I'd be more worried about 0 nitrates if that doesn't come up.

The tank is only about 2 months old. I'd imagine the 0 nitrates are due to the algae growth that I'm seeing currently. From my understanding algae will consume them. I also started with dry rock, so I'm sure there is absorption there too. They were 2.0ppm just last week, they've been coming down very slowly. Was close to 10ppm at one point. No ammonia present (detectable anyhow)

rhitee93 · Dec 6, 2023

every tank is different, but it sounds very similar to the trajectory I was on. After 3 months, my tank has slowly dwindled from around 9ppm to zero nitrates. Phosphates have hovered around 0.1ppm. For the last 2 or 3 weeks I was feeding 4 times as much food as before, and had started to decrease the filtration. I still hit zero nitrates.

It may have been coincidental, but a couple of days after I got to zero the brown slime bloom happened. I have a hunch it my be dinos because I would see stringy bubbles every once in a while, but I haven't tried that hard to ID it.

It took me a week to dose back up to around 10ppm, and I have been scrubbing the slime off daily. For the last several days, the slime has not been growing back after I scrub it off a surface, and it is receding on surfaces that I can't reach.

YMMV!

Spare time · Dec 6, 2023

Put the skimmer on a timer (on at night), dose aminos (when you get the coral), and put gfo in a bag into a filter sock.

mues · Dec 6, 2023

rhitee93 said:
every tank is different, but it sounds very similar to the trajectory I was on. After 3 months, my tank has slowly dwindled from around 9ppm to zero nitrates. Phosphates have hovered around 0.1ppm. For the last 2 or 3 weeks I was feeding 4 times as much food as before, and had started to decrease the filtration. I still hit zero nitrates.

It may have been coincidental, but a couple of days after I got to zero the brown slime bloom happened. I have a hunch it my be dinos because I would see stringy bubbles every once in a while, but I haven't tried that hard to ID it.

It took me a week to dose back up to around 10ppm, and I have been scrubbing the slime off daily. For the last several days, the slime has not been growing back after I scrub it off a surface, and it is receding on surfaces that I can't reach.

YMMV!

Will definitely be retesting from sump instead of display when I get home so I can verify the numbers... but the phosphate definitely spiked quickly. I have also been feeding what I would consider heavy, although that is only two cubes daily for 7 total fish.

EricR · Dec 6, 2023

I don't want to offer any bad advice as I don't consider myself that experienced.
I had the opposite problem at around the 6 month mark -- 0.00 ppm PO4 led to dino outbreak.
*when I dosed up phosphate, my nitrates started to plummet (assumption here is that some process which was phosphate-limited kicked in and started consuming nitrates but no idea if the opposite would play out in your case)

For algae, I vote manual removal.
Beyond that, I'd personally be leaning towards what rhitee93 said.

Uncle99 · Dec 6, 2023

mues said:
Will definitely be retesting from sump instead of display when I get home so I can verify the numbers... but the phosphate definitely spiked quickly. I have also been feeding what I would consider heavy, although that is only two cubes daily for 7 total fish.

.7ppm phosphate and zero nitrate seems an odd pair.
I would have thought high phosphate would bring at least, detectable nitrate.
Is that phosphate number correct at .7ppm not 0.07ppm which would be perfect, and then nitrate zero, possible.

mues · Dec 6, 2023

Uncle99 said:
.7ppm phosphate and zero nitrate seems an odd pair.
I would have thought high phosphate would bring at least, detectable nitrate.
Is that phosphate number correct at .7ppm not 0.07ppm which would be perfect, and then nitrate zero, possible.

The tester said .7 i reread it about 8 times because I was mindblown after it being undetectable last week. Will definitely be retesting tonight

ryanjohn1 · Dec 6, 2023

How often are you changing filter sock?

Court_Appointed_Hypeman · Dec 6, 2023

I would dose ammonium or nitrates to keep them measurable so the microbiome doesn't go all crazy.

mues · Dec 6, 2023

ryanjohn1 said:
How often are you changing filter sock?

I've only changed it once since I've had the tank up. Was visibly dirty. I've tried to let the tank be for the most part

mues · Dec 6, 2023

Court_Appointed_Hypeman said:
I would dose ammonium or nitrates to keep them measurable so the microbiome doesn't go all crazy.

My only issue with that is, I've got fish swimming happily currently. I'd think with the feeding and 7 fish in there it would be okay. They are smaller fish in a 150.... but still

ryanjohn1 · Dec 6, 2023

More regular changes of filter sock will bring down phos. I do mine every 2-3 days

Uncle99 · Dec 6, 2023

mues said:
The tester said .7 i reread it about 8 times because I was mindblown after it being undetectable last week. Will definitely be retesting tonight

Definitely, seems very weird to me.

Court_Appointed_Hypeman · Dec 6, 2023

mues said:
My only issue with that is, I've got fish swimming happily currently. I'd think with the feeding and 7 fish in there it would be okay. They are smaller fish in a 150.... but still

Ive got 9 one of which is large in a 75g and I dose about 2ml of ammonium chloride a day and still read 0 nitrates. I used to dose 17ml of neonitro with the same result.

It might help the phosphates drop to have available nitrogen, but it really depends on your biome, which we really don't have a way of knowing much about.

It's just what I would do in your situation, which is avoid being nitrogen limited.

Edit: to be clear, i mean I do not know if this is a good idea for you to try, and you have been doing this longer than I have, BUT i think being nitrogen limited can help cause a buildup of phosphates.

rhitee93 · Dec 6, 2023

Re: the feeding level - I have 5 smallish fish in a 120 and had resorted to 4 cubes a day of various frozen food, and couldn't get my nitrates to come up after a couple of weeks.