Problems with low Nitrate and high phosphate

[Gary LeCompte]

looking for some advice. I have been struggling with -0- Nitrates and high phosphates . If i remove my skimmer and add Chaeto. Will my oxygen level suffer? Would that be a good idea?

 

[BeejReef]

What is your typical phosphate reading Gary?
Are you running any other sort of nitrate media or filter aside from your skimmer? Are you carbon dosing?
How much livestock in what size tank being fed how often?

How old is your system and is it stocked with corals? I think removing the skim and adding a fuge would qualify as a pretty big change on a long-established system. Something you might want to do gradually.

An idea you might consider would be to add some chaeto and to run your skimmer part time.

 

[Gary LeCompte]

My Phosphate level yesterday was .08 ppm. I am running GFO and just changed it a couple of days ago. I can get my phosphate down to .03 ppm. but just briefly it seems, as to right after it get to that point it then rises to .18-.25 ppm. quickly. I am also running carbon in a duel reactor with the GFO. I am also dosing NO3 PO4-X trying to get the phosphates down. When I don't use anything Nitrates are still -O-. My tank is about 8 months old. It is a 180 gal. I had setup many years ago and lost it during Hurricane Katrina. I have about 12 fish medium size tangs mostly. My corals I just started putting some frags in a month to 2 months ago. The frag colors are diminishing and don't look like they should.
PH-8.08
Salinity 1.025
Alk. 8.62
Calcium 465
Mag. 1455
Nitrate -O-
Phosphate .09

I went bare bottom this time also.
3 1" Marine pure blocks in the sump with about 2 gal. spheres
Reef Octopus Regal 200 INT 8" Skimmer
Running Core 20 return pump
4 Maxpect Gyre 250 pumps for circulation running at approximately 60% ramping up and down.
3 Kessil AP-700 lights.

 

[BeejReef]

Sounds like a really nice setup! Beyond me tbh, but I think you'll get some insightful responses with all that background.
best of luck

 

[Dan_P]

My Phosphate level yesterday was .08 ppm. I am running GFO and just changed it a couple of days ago. I can get my phosphate down to .03 ppm. but just briefly it seems, as to right after it get to that point it then rises to .18-.25 ppm. quickly. I am also running carbon in a duel reactor with the GFO. I am also dosing NO3 PO4-X trying to get the phosphates down. When I don't use anything Nitrates are still -O-. My tank is about 8 months old. It is a 180 gal. I had setup many years ago and lost it during Hurricane Katrina. I have about 12 fish medium size tangs mostly. My corals I just started putting some frags in a month to 2 months ago. The frag colors are diminishing and don't look like they should.
PH-8.08
Salinity 1.025
Alk. 8.62
Calcium 465
Mag. 1455
Nitrate -O-
Phosphate .09

I went bare bottom this time also.
3 1" Marine pure blocks in the sump with about 2 gal. spheres
Reef Octopus Regal 200 INT 8" Skimmer
Running Core 20 return pump
4 Maxpect Gyre 250 pumps for circulation running at approximately 60% ramping up and down.
3 Kessil AP-700 lights.

You will need to find out what a good level for nitrate might be for coral. Dosing sodium nitrate would be the easiest way to achieve that level, but don’t forget to test nitrates more often to understand your system’s nitrate uptake which might change as PO4 begins to fall.

Dosing carbon (NOPOX) to reduce PO4 may not work without a higher level of nitrate. Bacteria will consume phosphate but at a much slower pace than nitrate. They just don’t need as much and none at all if they are nitrogen limited. GFO is the most straightforward way to reduce PO4 levels. Maybe your rock work is desorbing PO4. If so, reducing PO4 might take awhile.

 

[Gary LeCompte]

You will need to find out what a good level for nitrate might be for coral. Dosing sodium nitrate would be the easiest way to achieve that level, but don’t forget to test nitrates more often to understand your system’s nitrate uptake which might change as PO4 begins to fall.

Dosing carbon (NOPOX) to reduce PO4 may not work without a higher level of nitrate. Bacteria will consume phosphate but at a much slower pace than nitrate. They just don’t need as much and none at all if they are nitrogen limited. GFO is the most straightforward way to reduce PO4 levels. Maybe your rock work is desorbing PO4. If so, reducing PO4 might take awhile.

So are you saying , if I raise nitrates, phosphates could come down quicker than it is now?

 

[Dan_P]

So are you saying , if I raise nitrates, phosphates could come down quicker than it is now?

Yes, but in the context that dosing NOPOX is not the most efficient method to remove phosphate. GFO is better.

Full disclosure. The idea is that the bacteria will grow faster with a more available nitrogen source and use up the phosphate and hopefully not stimulate algae growth.

 

[Blizzahjh]

Dosing nitrate is all well and good and ive also done it in the past but maybe your color is washing is because those kessils are running way too bright. I have seen people with kessels wash their color out a bunch of times since kessels can pack a punch. I do not own or never have owned kessel so hopefully somebody else can chime in but my guess is its more your lighting than the nutrient levels. I constantly read 0 nitrate but i now have a reefbot so when i test it i can see the color change slightly day to day which means im measuring nitrates just the test kit resolution is too high to measure.

Be careful dosing nitrates, when i did mine i only added enough to go to 1ppm nitrate and it caused a massive drop in my phosphates (assuming) because 2 of my torches did polyp bail out. Corals can handle high'ish phosphate and be completely fine but they DO NOT LIKE quick drops in PO4. Take it slow if you go this route

If this was me i would stay the course with GFO, if you want to know why your phosphates might be rising it could be your old rocks leeching, try taking a rock out and putting it in a bucket with a powerhead and do a before and after, if you see phosphate go up then its your rocks and just running GFO will slowly fix the problem.

I might be wrong, but something to consider i suppose! Good luck!

 

[amoore311]

I have the same "problem". I always test 0 Nitrates (Nyos), and phosphates will be 0.3-0.4 when I test on Friday. I know there's nitrates in the water because the fuge is still growing sea lettuce and graccilaria.

I Dose Lanthum Chloride, because GF is not nearly as precise. Every friday I test PO4, if/when it reads high I dose Brightwell Phospate-E right into the skimmer. 2 Capfuls brings me to .08-.1 every single time without fail. I still confirm that with another Phosphate test 24 hours later.

 

[JSR]

Time to resurrect....

I have the same chemistry.
Tank is looking good; SPS etc growing well
So is this a “problem” that needs fixing.

I hate to chase the numbers.

 

[stripe14631]

Time to resurrect....

I have the same chemistry.
Tank is looking good; SPS etc growing well
So is this a “problem” that needs fixing.

I hate to chase the numbers.

What was your outcome I have a similar issue going on

 

[Randy Holmes-Farley Verified Community Expert]

Low nitrate and high phosphate can be dealt with in either of two ways:

1. feed more and phosphate
2. Dose nitrate and reduce phosphate

#1 requires more phosphate reduction efforts, but both work

#2 has more flexibility in the phosphate reduction method