High Phosphates need reducing?

  • Thread starter Thread starter bjsreefer
  • Start date Start date
  • Tagged users Tagged users None

bjsreefer

Equal parts fish and child wrangler
View Badges
Joined
Jun 3, 2025
Messages
789
Reaction score
581
Location
Florida, USA
Rating - 0%
0   0   0
I feel like I know the answer to this question but my phosphate in my 90g mixed reef continues to be high at .49. It hovers from .35-.5 and has been like that since the last week of July. When I first got the tank mid July the previous owner told me he had been around .7 and my first reading was .9 so definitely down since my additions. Most things are coming out and are healthy except a plate coral but it was already dying when I moved it in here, I’m running GFO and introduced macro… would y’all recommend getting a phosphate reducer to dose and try to get it to below .1 or just leave it as is?
 
Nitrate is really good at 23.9. It’s generally sat in the 20s since I’ve had it with a few readings in the teens and two readings in the very low 30s. But it’s consistent and hasn’t spiked at all, plus the phosphate is down by 60% of where it was when I got it thanks to the GFO and macro. I was already inclined to leave it alone because nothing seems angry at all and I’m paranoid of overdoing it like I did with my nano and had a short minor dino outbreak. Just wanted to make sure I wasn’t poisoning anything. I have zero algae issues at all and any algae that I do get, my two tangs and starry blenny gobble up before I ever see it.
 
I feel like I know the answer to this question but my phosphate in my 90g mixed reef continues to be high at .49. It hovers from .35-.5 and has been like that since the last week of July. When I first got the tank mid July the previous owner told me he had been around .7 and my first reading was .9 so definitely down since my additions. Most things are coming out and are healthy except a plate coral but it was already dying when I moved it in here, I’m running GFO and introduced macro… would y’all recommend getting a phosphate reducer to dose and try to get it to below .1 or just leave it as is?
When phosphate is above say .2ppm, I use an LC product like Phosphate-E and a really tight sock, once, every second day until I reach .2ppm as GFO is as you know very expensive.

For me, above .5ppm over months seems to darken some sticks in my system.

I dose the LC at night and pull the sock in the morning.

I can drop phosphate by about 33% each treatment and it’s so much cheaper.

Then at .2ppm, I use a GFO to lower and maintain .1ppm. I never go lower than .1ppm as I never want zero and testers have margin of error.

I ve been using .1ppm for 7 years now.
 
I feel like I know the answer to this question but my phosphate in my 90g mixed reef continues to be high at .49. It hovers from .35-.5 and has been like that since the last week of July. When I first got the tank mid July the previous owner told me he had been around .7 and my first reading was .9 so definitely down since my additions. Most things are coming out and are healthy except a plate coral but it was already dying when I moved it in here, I’m running GFO and introduced macro… would y’all recommend getting a phosphate reducer to dose and try to get it to below .1 or just leave it as is?
When phosphate is above say .2ppm, I use an LC product like Phosphate-E and a really tight sock, once, every second day until I reach .2ppm as GFO is as you know very expensive.

I dose the LC at night and pull the sock in the morning.

I can drop phosphate by about 33% each treatment and it’s so much cheaper.

Then at .2ppm, I use a GFO to lower and maintain .1ppm. I never go lower than .1ppm as I never want zero and testers have margin of error.

I ve been using .1ppm for 7 years now.
That’s the only thing I was considering. And I run a reef mat so no filter sock required.. or possible on the drain hah
 
Chemi pure elite and LaCl all you need
 
That’s the only thing I was considering. And I run a reef mat so no filter sock required.. or possible on the drain hah
I dose LC in the reef mat but dose 1/3 to 1/2 of the recommended and I do that as needed daily until it reaches the range I am aiming for.
 
What is the nitrate level? That may impact the best methods to use.

IMO, you need not reduce phosphate. My target level runs up to 0.3 ppm, and some nice tanks have 1 ppm

This has more:

https://www.reef2reef.com/ams/randy’s-thoughts-on-nutrient-target-ranges.1087/
This post was very helpful; thanks.
I have a newly set up 40gal tank less than 1 month old. PO4 is .33ppm via Hanna checker. The tank is full of Gulf live rock and sand, and includes some hitchhiker corals and other life. I added 7 Astraea snails plus 2 peppermint shrimp. I haven’t fed the tank except to add Algaebarn’s copepods (one jar, added at one time) and 10ml phytoplankton per day.
I was concerned about the high phosphate as it did climb initially to 0.55. After two 10% water changes over a week’s time, it’s now .33. From your articles, I will now worry a bit less about this. As a beginner, I thought I was supposed to see phosphate at 0.05ppm, not 100x higher!
 
I bought a cheap hang on filter, threw a bag of GFO (used BRS to get correct amount) ran it for a couple days and my phosphates went from .31 to .11. I tried almost every other chemical
Remedy out there and nothing worked like I wanted. My phosphates stay at .11 and when they start to creep up I just reload the GFO and “poof” back to .11. My nitrates are at 12.5
 

TOP 10 Trending Threads

WHAT MOST EARNS A REEFING BUSINESS YOUR "BEST OF THE BEST" NOMINATION?

  • Excellent livestock or product quality

    Votes: 8 24.2%
  • Honest listings and accurate expectations

    Votes: 3 9.1%
  • Helpful, knowledgeable customer service

    Votes: 3 9.1%
  • Standing behind a product when something goes wrong

    Votes: 7 21.2%
  • Fair prices and good value

    Votes: 6 18.2%
  • A unique selection or innovative products

    Votes: 0 0.0%
  • Supporting the reefing community or sustainability

    Votes: 0 0.0%
  • Consistent quality over time

    Votes: 5 15.2%
  • Other (Post in the comments)

    Votes: 1 3.0%
Back
Top
Home
Post thread…
Market
What's new