Really confused on nitrate and phosphate levels for SPS

JammyBirch

Aquaria Engineering
I'm seeing all kinds of posts about needing some phosphate and nitrate for good growth and others that are trying to get rid of both, especially phosphate.

I thought phosphate limited the SPS coral to utilize calcium for growth so a zero level is what is needed... Nitrate i can understand but to what level?

Any comments?
 
If your phosphate is a true zero for any length of time, you can pretty much forget about sustaining life. Detectable to about .10 is usually just fine for SPS, and many people have thriving SPS tanks with levels higher than that.
 
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Most sea life require carbon, nitrogen, and phosphorous to exist. We cannot as hobbyist measure nitrogen and phosphorous so we measure nitrates and phosphates. If you take any one of these three to absolute zero most life will die. There are some rare exceptions I think , not a biologist so this is not my area of expertise. A lot of tanks say that these things are "undetectable", that doesn't really mean zero. Test kits, even Triton testing, has detection level limits which limit how low they can detect. Also remember your measuring whats in the water column, not the animals. Therefore if your balance of supply and demand is perfect you read near zero on most hobby kits. Thus why some believe high import and high export is the way to go, giving everything enough and removing all excess therefore there's not much in the water column to measure.
 
Well I ordered a Hanna phosphate and an alkalinity tester, so I should be able to test more accurately. I'm judging phosphate/GFO replacement based on how often I'm cleaning the glass. Titration, counting drops, is a little annoying too.
 
I thought there is always a presence do to the production of said thing in the tank it's self. As low as it may be it is in your water till it gets absorbed via reactor or other method. But please correct me if I am wrong.
 
Honestly it seems that SPS keeping is the most difficult of all corals. I've been reading these posts on here for days now and see that many beautiful tanks have crashed unexpectedly. That is a shame, and a little scary. I have one SPS so the adventure begins...

Does anyone on here keep SPS dominant reefs in nanos? I'm most concerned about the small volume and increased potential for parameters to go nuts. Most of the threads I'm reading are about tanks that are 120g or larger. I'm beefing up my measurement capability for sure.
 
I thought there is always a presence do to the production of said thing in the tank it's self. As low as it may be it is in your water till it gets absorbed via reactor or other method. But please correct me if I am wrong.

I am not sure where your going here. Whether they are created in tank or added if your stripping the water so fast that the animals(corals) dont have time to absorb enough then your depriving them. If you let them sit in a nutrient soup of excess then whatever they don't use will be leftover to feed things like algae. It still comes back to a balancing act.
 
I am not sure where your going here. Whether they are created in tank or added if your stripping the water so fast that the animals(corals) dont have time to absorb enough then your depriving them. If you let them sit in a nutrient soup of excess then whatever they don't use will be leftover to feed things like algae. It still comes back to a balancing act.

What I am trying to say in a round about way is there is never 0.00 in the tank. It is being produced all the time and the time between being produced and being removed it is in the water.
 
Honestly it seems that SPS keeping is the most difficult of all corals. I've been reading these posts on here for days now and see that many beautiful tanks have crashed unexpectedly. That is a shame, and a little scary. I have one SPS so the adventure begins...

Does anyone on here keep SPS dominant reefs in nanos? I'm most concerned about the small volume and increased potential for parameters to go nuts. Most of the threads I'm reading are about tanks that are 120g or larger. I'm beefing up my measurement capability for sure.

Look up user name taphil, he had one of the nicest tanks you will ever see in a nano. I do believe it ended up crashing eventually. Worth looking at though.
 
Got the Hanna phosphate tester today, the powder reagent is not great but it wasn't difficult. Read a 0.00, which tells me it's pretty low...I know it's not zero, I have some stuff on the glass but I think I'm in good shape.
 
I was/am in the same boat. Corals are growing, polyp extension is awesome, but colors are pale. Nitrate/phosphate is 0 regardless of what I add (fish, food, amino etc). Played around with those for a couple of months. Finally got my flow/amount of gfo dialed in to keep my po4 where I want them but can't get a nitrate to register to save my life.

about 2 weeks ago I trimmed back my chaeto (to much apparantly) and have been battling what looks to be diatom hair algea or a brown cyano (it's stringy, blows off the rocks easily and is brown).

Seems to be going away slowly, but I am following along on this one for other ideas.
 
If you have any macro algae or nuisance algae it will interfere with organic phosphate testing. Algaes thrive in the presence of nitrate and phosphate, so much so that if you have enough, your tank can be producing a ton of PO4 but consumed so quickly and constantly by algae the test will read 0.00. That's what we call algal interference. Moreover, a tank too clean for algae to grow is too clean for corals to grow as well
 
Listening in curiously in since I am also in same boat. Times two.

I just bought a Hanna Phosphate kit yesterday, since I couldn't get a reading on my Salifert kit. Figured I would get a reading on the Hanna. Nope. Hanna also read 0.00 ppm
Read in Hanna manual that accuracy is +- 0.04ppm +-4% (So if I'm between 0 and 0.03, I could potentially get a 0.00 reading). Did I understand that correct?
Was considering the Hanna Phosphorus tester instead, which reads in ppb, but was advised not to go that way.

Also got a Salifert Nitrate Kit, since wanted to also check this.

[TANK#1]
65Gal (SPS only) Frag Loaded 9mnth old tank, which has No algae problems.
SPSs are doing fine. Very nice polyping after I got all parameter stable just recently. 3 fish.

Phosphate 0.00
Nitrate 0.0




[TANK #2]

90 Gal (Mixed Soft/LPS) 15 yr old tank, which will be rebuilt (running Fallow for a few weeks due to all fish dying).
Tank is Wrapped DARK to kill off all (Cyano, + Green Algae problems) .
All Corals out and in a holding tank. Rocks are sparkling clean/algae free after 2 weeks in darkness. Some Coraline loss.

Phosphate also 0.00
Nitrate 5.0.



Reason for interest in both Phosphate & Nitrate is when I start-up Tank #2, add corals back, and start with fish again.
Hoping my past Algae / Cyano problems will be gone (with many adjustments I'm making; Improved Circulation, added GFO reactor, Rocks scrubbed, cleaned, and starved from light).
 
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I have hanna 713 which always reads 0, in my system the 736 is much more useful. It gives me a more accruate reading. The way I use the 736 is: I let the reagent in the vial for at least 10 mins before testing. You most likely do not have 0 phosphates if you feed your tank. After feeding phos can jump from .01 to .06. In my tank I try to keep phos 10ppb or less with hanna 736 tested in the am prior to feeding.

I think it is easier to keep colorful acros with really low phos and some nitrate.
 
Toothman,

Same here. the 713 gives me 0. I feed moderately with fine particle foods like oyster feast and coral frenzy, and I have excellent colors on my acros and LPS.

and ND nitrate level either.

Its about Balance.

Find the best husbandry regiment that works for you and stick to it!
 
Think about what's going on in the sea water surrounding a healthy reef. Nitrate and phosphate levels in natural sea water are quite low in most circumstances. Most of the available phosphate and nitrogen is tied up in phyto- and zooplankton and this is what corals feed upon. So reefkeepers try to mimic natural conditions without the plankton and it leads to starvation and this can lead to disaster. Feeding and maintaining water quality is a delicate balance. Find what works for you based on your filtration, water changes, and feeding regime.....................Jim
 
When my tank doesn't look just right, I do the old stand by; water change. How simple. A 10% change always perks thing up.
 
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