How to manage sustainable, low phosphates but not zero.

[Fisherman Joe]

Its been a rather fascinating project this. Testing PO4 daily takes 3 minutes but not doing it for a few weeks can lead to issues that take months for corals to regrow.

Interestingly now, those patches of Cyano have gone. My PO4 is still 0.04.

I recall some local fish stores telling me to aim for zero phosphates a while back. That’s why I was hesitating.

My nitrate is around 5ppm and I’m seeing almost zero growth of gunk on the aquarium glass in over week. Is this typical?

When my PO4 was zero and my NO3 was 10ppm. I would need to clean the glass each 48hr.

Why is that?

 

[legrunt]

Strange... My no3 is 4ppm and my po4 is 0.06 and I'm cleaning my glass every 2 days...

 

[PeaBrain]

I feel like a lot of people have been scared into running higher nutrients. I am running my tank like it’s the 90s. I won’t be dosing any po4 I am sure of it. And I will most likely be running gfo for a while. I won’t let a 0 reading make me change anything I have been doing for all these years. My fish love it when it’s reading zero because they just get extra food
I feel bad for the people who are cought up in dumping po4 into their tanks daily. We never used to have to do that and I am curious as to why so many people feel like they have to do this now.

I have decided to dose PO4 and NO3 recently and I have seen almost immediate improvements in SPS growth and color. I don't feel like I have to, but I like the results.

 

[Fisherman Joe]

So, Day 7 (perhaps, i havent really been counting).

Each morning at 9am I test my PO4, and its been steady at 0.04 with only my flake being fed (automatically) 4 times a day.

Yesterday i tried to something new, I fed some live phytoplankton from the fridge (a bottle i ordered from from eBay) and today my PO4 is 0.09.

I dont know if its the plankton, or an accumulation over time thats led to the increasing PO4. Today i wont feed anything but flake and i have added 10ml (in my 600L or 120G tank) to see if the bacteria can bring it back down.

Are swings in PO4 when its > 0.1 ok?

 

[Fisherman Joe]

Having read some of Randy's articles, i think dosing a carbon source is likely to strip far more nitrate from the system than phopshate.

I will measure tomorrow and add GFO rather than dosing carbon.

Still unsure if the swings in PO4 are healthy, going from 0.04 to 0.09 overnight.

 

[Fisherman Joe]

Ok. After dosing Vodka and vinegar, surprisingly my NO3 is solid at 5ppm. Maybe even increased a little to 6-7ppm and my PO4 has dropped back to 0.02.

I will continue to monitor daily and feed accordingly.

Should I maybe get in the habit of adding a little Carbon dosing with food or shortly after?

The water is a little cloudy now, as to be expected.

Are the PO4 swings from 0.02 - 0.09 acceptable?

 

[Fisherman Joe]

What weight do people put on maintaining a redfield ratio of Carbon, Nitrogen and Phosphorus in the tank?

Interesting:
https://www.triton-lab.de/fileadmin...IOS/Triton_Tech_Paper_-_TRITON_Ratios_1.2.pdf

Given my PO4 is around 0.04, my NO3 (According to the Redfield ratio) should be 16 x this, so 0.64 NO3.

Those nitrates seem low, mine are at 5ppm at the minute. Thoughts?

Also given that PO4 swings around faster at lower levels, what will SPS think of this?

 

[Fisherman Joe]

Hi all.

My PO4 is now sitting at 0.09 with the only the refugium exporting nutrients. I have stopped dosing carbon and removed the GFO.

How should I get this down? Would you dose a little carbon to help it down or turn up the refugium light and be patient?

I have an AI Fuge light and it’s on 12 hours for 50%. I just increased this to 55%.

 

[esther]

Hi all.

My PO4 is now sitting at 0.09 with the only the refugium exporting nutrients. I have stopped dosing carbon and removed the GFO.

How should I get this down? Would you dose a little carbon to help it down or turn up the refugium light and be patient?

I have an AI Fuge light and it’s on 12 hours for 50%. I just increased this to 55%.

I'm in the same boat, but am terrified of removing the ROWAphos. I'm consistently between .08 and .11 using the ROWAphos and renewing every two weeks. Are your phosphates 0.09 because of feeding? I feel like if you have it there and it's consistent and everything looks good, why add stuff to the tank?

 

[mitch91175]

Hi all.

My PO4 is now sitting at 0.09 with the only the refugium exporting nutrients. I have stopped dosing carbon and removed the GFO.

How should I get this down? Would you dose a little carbon to help it down or turn up the refugium light and be patient?

I have an AI Fuge light and it’s on 12 hours for 50%. I just increased this to 55%.

From what you have posted about your system, if I were in your shoes I’d do something like feed 1 cub frozen and some flakes in morning/evening. Feeding each once per day. It seems that your PO4 was reducing and staying within a range that seems acceptable.

if you have a lot of fish to feed and if some are tangs, just add in one seaweed feeding daily/every other day.

You can control your PO4 via feeding appropriately. If it gets out of hand you can just cut back on feeding frozen for instance for a few days.

I have 6 pretty decent sized tangs that only get half clip seaweed and a manageable tumble of pellets each day. Until I did this nutrients were always a problem. Fish aren’t starved either since they graze all day long.

I have dosed PO4/NO3 and still have the capacity but controlling first via nutrient import/export and have those as backup just in case. I’d rather use them to get back on track than adjusting my feeding. Feeding amount will be adjusted as tank determines necessary.

 

[Fisherman Joe]

It seems that when I feed frozen food PLUS dose NO : PO X, it seems that keeps the PO4 low (~0.03) But i'm worried that its depleting my NO3, a few weeks back it was 0.0. ATM my NO3 is 5ppm.

I want to get to a point where my refugium can manage the PO4. Therefore i need to let my refugium catch up. I could dose lanthanum but I've never done that I've heard mixed things.

I can reduce feedings of frozen, but i cant do it forever.

 

[mitch91175]

It seems that when I feed frozen food PLUS dose NO : PO X, it seems that keeps the PO4 low (~0.03) But i'm worried that its depleting my NO3, a few weeks back it was 0.0. ATM my NO3 is 5ppm.

I want to get to a point where my refugium can manage the PO4. Therefore i need to let my refugium catch up. I could dose lanthanum but I've never done that I've heard mixed things.

I can reduce feedings of frozen, but i cant do it forever.

How many fish are you feeding and what type of fish/size? From what I read it does seem like your system is already dealing with PO4 when you do not mess with it. NO3 isn't a problem for you it seems and likely no need to dose NOPOX.

Didn't you say that PO4 read 0.0 then after feeding is read 0.06 or something like that? Then 10 hours later it was back down to 0? If that is in fact what you mentioned or close, then feeding twice a day should work and keep you with PO4 in the system. NO3 should be dealt with using the refugium mostly.

Dosing lanthanum chloride isn't a big deal as long as you know what you are doing. If you use commercial products they have a foundation of LC anyways (at least I believe).

Right now I'd say forget about chemical solutions and focus on what you can do with controlled feedings. There are some days that I forget to feed my fish (not intentionally). They are just fine. I recall reading somewhere about fish will eat as long as you feed them. It makes sense cause every time I feed, seems like at least 2-3 fish take a crap releasing nutrients into the system.

 

[Fisherman Joe]

I have about 12 fish atm, with the biggest being a yellow tang. Some clowns, a coral beauty, 3-4 wrasse and a couple of gobys and 4 anthias.

When i just feed flake and pellets (4 times a day) for the anthias my PO4 slowly creeps up over time without GFO. I have been running it but it depletes my PO4 to zero.

Also, not running GFO i am not really feeding reef roids or cultures phyto and even the occasional (twice a week) frozen cube of mysis or brine shrimp, i worry i'm not feeding my corals enough and some of the meatier foods for the slower fish like my bangai cardinal.

I have been dosing NO : PO X to help feed to corals AND get my nitrates down a little, they were at 10ppm.

Randy since said 10ppm is fine, but i have always tried to keep them at 5ppm.

I want to be able to have my system (refugium) take over my PO4 management alone and atm, its swinging all over. My PO4 migrates to 0.0 if i don't feed anything extra (on top of my flake and some pellets are in the same tub on an Eheim automatic feeder, which is my default). BUT when i feed a little more, i seem to get spikes of PO4 and Cyano bacteria over time.

My question is this, will the swings in PO$ from 0.0 > 0.9 upset my SPS?

Do i just need to be patient and let my refugium take over the management of this to keep it in check OR will i need another method for controlling PO4 at stable low levels?

 

[mitch91175]

This is a good list of things to do for PO4:

 

[mitch91175]

I have about 12 fish atm, with the biggest being a yellow tang. Some clowns, a coral beauty, 3-4 wrasse and a couple of gobys and 4 anthias.

When i just feed flake and pellets (4 times a day) for the anthias my PO4 slowly creeps up over time without GFO. I have been running it but it depletes my PO4 to zero.

Also, not running GFO i am not really feeding reef roids or cultures phyto and even the occasional (twice a week) frozen cube of mysis or brine shrimp, i worry i'm not feeding my corals enough and some of the meatier foods for the slower fish like my bangai cardinal.

I have been dosing NO : PO X to help feed to corals AND get my nitrates down a little, they were at 10ppm.

Randy since said 10ppm is fine, but i have always tried to keep them at 5ppm.

I want to be able to have my system (refugium) take over my PO4 management alone and atm, its swinging all over. My PO4 migrates to 0.0 if i don't feed anything extra (on top of my flake and some pellets are in the same tub on an Eheim automatic feeder, which is my default). BUT when i feed a little more, i seem to get spikes of PO4 and Cyano bacteria over time.

My question is this, will the swings in PO$ from 0.0 > 0.9 upset my SPS?

Do i just need to be patient and let my refugium take over the management of this to keep it in check OR will i need another method for controlling PO4 at stable low levels?

I have a lagoon that has 4 Bartlett anthias, 2 tangs, 2 dwarf angels, and a blenny. They all do their jobs, eat algae and whatever I feed the tank. I only feed them once a day pellets by hand. Not a lot either and they are all healthy. No pinched stomachs either.

This just help control nutrients.

I think that what the issue is that you aren't familiar with your system and the coral you are keeping. Or it may be that you just feel you have to do something to the system.

Are you experiencing any deaths, etc? Color problems? No polyp extension?

 

[mitch91175]

Forgot to mention. PO4 will forever fluctuate to an extent in your system. Do not freak out if it gets to 0.1ppm. Do not freak out if it gets to 0ppm.

Just do your best to maintain levels that you see work for your tank. Observe your coral at each level for a bit then decide what works for you and how you want to maintain your system. Making too many changes too frequently will do more harm to your coral and cause more frustration on your part.

 

[Fisherman Joe]

Thanks for the advice. I’ve had various tanks for a while now so I’m pretty familiar with the basics but it never hurts to remind yourself. So thanks.

What I’m really after is sustainable, low phosphates, ideally without using media or dosing carbon, as stated above.

I know Anthias are active fish so need several feeds a day, ideally. I have lost a few of the smaller ones a while back.

Without feeding frozen or any coral foods, I’m holding my PO4 at 0.09.

Nervous to feed anymore. I’m hoping my refugium will grow in more. It’s pretty big. I’m not convinced a refugium can manage PO4 alone.

 

[Fisherman Joe]

The tank

 

[mitch91175]

Looks fine to me. You have sand too so that will contribute to fighting PO4. Where you are seems fine to me just stay in a range around there, say 0.07 - 0.12. Closer to the low end obviously better but then your not chasing "A" number.

 

[Fisherman Joe]

True but like I said, I get Cyano when it’s close to 0.1

I’ve increased the flow as much as I can.