0 Phosphate Issue

[jhatfield]

I understand that there should be a balance/ratio between phosphate and nitrate for coral health (correct me if I'm wrong.) My phosphate has always been 0 (hana low range) while nitrate has typically been around 10. How do you raise phosphate slightly without impacting nitrate?

Further, I want to avoid making my current algae issue worse. Not exactly sure what kind of algae it is but it's a bright vivid green film covering the topside of the rocks. Snails appear to be eating something but have no impact on the amount of algae.


Tank details
This is a 43 gal 3 month old tank with a few small frags and no fish. The past two weeks have, by far, been the most stable with very little fluctuation from the numbers below. The corals have been in there a month and are open but cannot determine if there's signs of growth yet or not.

• Nitrate 6
• Phos 0
• Alk 8.2
• Cal 425
• Mag 1330
• SG 1.025
• Skimmer and a carbon reactor
• weekly 10% water change

 

[Randy Holmes-Farley Verified Community Expert]

I understand that there should be a balance/ratio between phosphate and nitrate for coral health (correct me if I'm wrong.)

I actually don't agree. It's become trendy to claim that, but there's no reason to think it true that I have seen or that makes scientific sense.

There are levels that are too low of each and clearly cause issues. There are also levels that are too high and cause issues.

There's not a reason to think that the optimal levels of nitrate for the health of an individual coral changes as the level of phosphate that happens to be in the water changes. Same the other way around. If nitrate was 0.00000001 ppm, is it optimal for phosphate to be 0.0000000002 ppm? And if nitrate is 500 ppm, is it optimal for phosphate to be 3 ppm?

The goal (IMO) should be to have optimal levels of each, not to peg a particular ratio as desirable.

So should you do anything to boost phosphate? That's trickier with an algae issue as boosting it may cause the algae to grow even faster. Is there an apparent problem with coral health at the moment?

 

[jhatfield]

Is there an apparent problem with coral health at the moment?

Nothing obvious other than not growing. Being new, I'm still trying to figure out what normal is in terms of how the corals appear but most corals seem happy judging by the color. Alveopora is out waving and colorful while the zoa I got last week only opens occasionally. The older zoas, galaxea and a stylopora frag have been in there a month, look good but I haven't seen growth. Acans receded a bit after being placed in the tank (1 month ago) are currently showing ok color and seem to be hanging in there.

The one coral death I had was a euphillia that died within a couple days of being placed in the tank either by a rogue peppermint shrimp or some disease/bug that made it melt away over a period of a couple days.

 

[Sabellafella]

Nothing obvious other than not growing. Being new, I'm still trying to figure out what normal is in terms of how the corals appear but most corals seem happy judging by the color. Alveopora is out waving and colorful while the zoa I got last week only opens occasionally. The older zoas, galaxea and a stylopora frag have been in there a month, look good but I haven't seen growth. Acans receded a bit after being placed in the tank (1 month ago) are currently showing ok color and seem to be hanging in there.

The one coral death I had was a euphillia that died within a couple days of being placed in the tank either by a rogue peppermint shrimp or some disease/bug that made it melt away over a period of a couple days.

You could try going heavy on flake and pellet food.

 

[Dr. Reef Verified Sponsor]

By the way if you are using hanna phos low range and it's showing 0 that doesn't mean it's really 0. Low range unit cannot measure ultra low levels.
There is a unit for that it's hanna phos ultra low hi 736. That will break it down in much lower range.
What r u using to rid phos?
Btw 1 month is hardly enough time for some corals to even get use to a new tank let alone grow.

 

[jhatfield]

There is a unit for that it's hanna phos ultra low hi 736. That will break it down in much lower range.
What r u using to rid phos?

I'm not using anything to get rid of phosphate. I assumed that there must be some trace of phosphate in spite of what the checker was reading. Just surprised it's still not readable after my (less than stellar) cleaning regime.

Btw 1 month is hardly enough time for some corals to even get use to a new tank let alone grow.

That's good to know. I'm finding one of the biggest challenges in the hobby is determining what is normal and not.