I'm dying on this hill - Phosphate is more important than alkalinity

[sde1500]

For those of you that concentrate on the numbers so closely, is it an enjoyable part of the hobby for you? I'm genuinely curious because I hate testing and trying to tune into numbers but only because I find it boring. I leave my tank be and respond if something seems to not be well. I'm definitely not saying my way is better, it works for me and it's just how I enjoy the hobby. I see people post spread sheets and formulas and exact parameters and stress when they are .0X off and it makes me cringe because I wouldn't enjoy the hobby that way. So my question is for those of you that like to test frequently and keep exacting water results, do you do it because you enjoy that part of it or are you afraid the tank will fail if you don't do it that way?

I test nearly every day right now as I work to dial in my switch from water changes to dosing. But I also don't think I chase numbers. Kinda just found a few of the big numbers my tank was running while doing water changes and sought to maintain them while dosing. Admittedly, I don't even know my phosphate level. Probably the next number I should learn. But while I don't find testing all that enjoyable, and I'm sure I'm not alone with this, I find tinkering with my tank fun. Testing the tank and maintaining target numbers is just one way to do that.

 

[living_tribunal]

I gather you are in this field of study? I did the neuroscience grad school thing... and think it would be pretty neat to do some more academic work in the marine hobby world. So many angles to explore.

I am not, I am a software developer. The data is compelling enough to at minimum explore however.

 

[Chaz D]

Trying to now translate it into application. Will be interesting to see how it works out long-term.

For anyone interested, I'm running nitrate of .5-1 and phosphate of .15. I'm able to keep levels +- 10% at all times via vinegar dosing and fuge, that's all.

Where are you running alkalinity? Curious that doesn't get mentioned anywhere in the articles. I think this is especially important given the way we most run our tanks...low nutrients/low alk OR high nutrients/high alk. Maybe more to this.

 

[phillygeeks]

Nice observation OP. Definitely something to think about.

 

[Fourstars]

I found the same with my tank. just never really had the colors others had till I started dosing phosphate and nitrate. Those who think they can manage a reef tank without testing are setting themselves up for failure. That being said, I only find the need to test every month unless I visually see issues, then test kits come out.

 

[living_tribunal]

Where are you running alkalinity? Curious that doesn't get mentioned anywhere in the articles. I think this is especially important given the way we most run our tanks...low nutrients/low alk OR high nutrients/high alk. Maybe more to this.

I don’t believe the absolute level of alk has an impact on the efficacy of coral symbiosis utilization of phosphate.

The processes for alk consumption are different for phosphate consumption.

I run alk at 9.

 

[Potatohead]

If phosphate is the limiting nutrient, at 0.01 to 0.02 ppm phosphate it is, alkalinity higher than 7° dKH is of no use. In contrary most probable it will worsen things and may induce STN of SPS from the base.

In my opinion 0.05 to 0.1 ppm of phosphate is the safest range. You have at least 0.04 ppm range before it is really getting bad.

However, dropping phosphate concentrations may always be a problem. In contrast rising phosphate concentrations hardly ever will cause problems and only with extremely high concentrations. The problems will occur when you lower phosphate concentrations again. SPS adapt to high phosphate concentration rapidly but are really bad in adapting to lower phosphate concentration.

Skeletons of SPS show quite high phosphate concentrations (even at low phosphate concentrations in the water). Phosphate is located mainly in the organic matrix. Obviously phosphate plays a crucial role in skeletal growth. Especially the fast growing SPS need a lot of phosphate and now it also gets clear why raising alkalinity at low phosphate concentrations has such a detrimental effect.

At higher phosphate concentrations also higher alkalinities may have a positive effect for coral growth, but only then.

I feel like I've made it when I have Mr Balling responding to one of my threads

I was slowly losing my sps coral and put it down to alk being around 6.8-7.2. I then learnt that it was zero phosphates and very low nitrates. The sps was getting pale then stn, my lps were also not as puffy, I now dose potassium phosphate at a dose of 1.3mm on my system (90litre) 0.08 every other day as I don't want to over do it. The tank looks happier just still not as puffy as I'd like.
Does anyone know to what level you can raise per day? I'm assuming there are other organisms within the tank that use phosphates other than corals, and I assume that the rocks and sand bind some also. I am just wandering if the tank will reach a balance and dosing will only be required occasionally not all the time or is it a case that's it full time and on a doser? This is all fairly new to me.

You can dose as much as you need to get the levels where you want in the water. Over time you will need to dose less as things stabilise.

 

[EJReef]

I test so I can know what the nutrients levels are testing at. As things change I adjust to keep the corals fed. If I don't test then I am guessing that levels are ok and that works until it doesn't.

I recently brought home a piece of dry rock and dropped it in a bucket with RODI (tested zero Phosphates to start). I retested in a week and got 4ppb (HannaULR). Retested a week after that and got 15ppb.

Hypothesis: Phosphate in reef tanks settles on substrates. Dosing may not cause steady measurable increases as the phosphate present is apparently absorbed by the rock in the system. When the system reaches capacity to accommodate phosphate then dosing a small amount could cause significant non-linear concentration increases.

Did it have dead stuff on it?

 

[EJReef]

Random side question - why does phosphate drop when nitrates spike?

Because biological processes need both and there's an abundance of nitrate vs phosphate

 

[living_tribunal]

I don’t believe the absolute level of alk has an impact on the efficacy of coral symbiosis utilization of phosphate.

The processes for alk consumption are different for phosphate consumption.

I run alk at 9.

Just wanted to note, I believe any kind of indirect interaction between the two will of course impose on the efficacy of the other if there is a deficiency, just for the sticklers out there. @Hans-Werner had a better explanation breaking this down.

 

[KrisReef]

So i have been conducting a secret experiment on my po4 levels since iam trying to rehab a bleached non acclimated wilsoni to a tropical tank. Those things eat like there is no tomrrow and i do my best to target feed but this extra feeding has shot my po4 to levels that have been outright terrifying but everything in the tank as seemed to love it.

Put a water glass over the Wilsoni t

Did it have dead stuff on it?

Nope, it looked like a naked piece of sandstone(aragonite) from a dry rock mine. No stains or water marks.

 

[Ernie C]

Any suggestions on which phosphate additive to use that can be easily ordered online or found locally?

 

[Phildago]

I mean, this is definitely comparing apples to oranges.

Alkalinity is directly used to build the Skeleton, phosphate is a nutrient. For sure phosphate is super important, but so is alkalinity.

 

[Birdbrains?]

My tank has been running for about three years. It is acro dominated and for the most part has done ok. I have always thought my growth was a little slow, and colors were just alright. Maybe like a C+ grade.

My parameters are always quite stable, and I run my alkalinity in the low 7's. I have experimented slowly raising it to the mid 8's for a few months and really noticed hardly any difference, but because it didn't seem any better I slowly dropped it back down. My nitrate is pretty much always 4-5 and my phosphate was always .01-.02 range. I knew this was perhaps slightly low but still in acceptable range.

In my quest to deal with some dinos in the sand, since I had a spare head on my doser, about four weeks ago I started dosing phosphate. I started at dosing about .06 per day. Four weeks later I am dosing .2 per day, which is actually maintaining about .06 actually in the water.

The difference in my corals is profound. Color, polyp extension, growth, all seemingly exploded in about a week. Coralline growth has probably doubled as well. Euphyllia much puffier and also growing faster.

There is probably some bias here, and this probably differs based on each individual tank... But the difference I am seeing based on phosphate levels compared to alkalinity level, and even alkalinity stability is immense.

Nothing beats a varied diet

 

[Potatohead]

Any suggestions on which phosphate additive to use that can be easily ordered online or found locally?

If you want a prepared product, Seachem Flourish Phosphorous or Brightwell NeoPhos are popular.

You can really use any sodium or potassium based phosphate chemical. I use trisodium phosphate.

I mean, this is definitely comparing apples to oranges.

Alkalinity is directly used to build the Skeleton, phosphate is a nutrient. For sure phosphate is super important, but so is alkalinity.

As Hans-Werner said earlier, phosphate is also present in coral skeletons, in quite high concentrations.

 

[living_tribunal]

Any suggestions on which phosphate additive to use that can be easily ordered online or found locally?

Bunch of em’ the two most people use are neo phos from brightwell and seachem flourish phosphorous.

 

[living_tribunal]

It’s so good to see the phosphate love here.

This conversation was brought up in another thread, I simply posted the science I did above, thought others might be interested in it.

Was met by a squad of aggressively passionate individuals who said science is useless and proceeded to insult anyone who questioned their narrative.

Seems like there are some flat earthers into reefing.

 

[living_tribunal]

@Scrubber_steve seems like there are more anecdotal reports of users seeing happier corals with elevated phosphate levels.

What do you think of this?

 

[KrisReef]

It’s so good to see the phosphate love here.

This conversation was brought up in another thread, I simply posted the science I did above, thought others might be interested in it.

Was met by a squad of aggressively passionate individuals who said science is useless and proceeded to insult anyone who questioned their narrative.

Seems like there are some flat earthers into reefing.

The earth is mostly flat or else our tanks would leak?
Science is generally correct but application is often sketchy, IMO

 

[living_tribunal]

The earth is mostly flat or else our tanks would leak?
Science is generally correct but application is often sketchy, IMO

This is true, but saying science is completely useless and providing a picture and caption as a rebuke is the very definition of ignorance.

I'm open to testing any kind of new method if the evidence is compelling and within reason, no reason to be emotionally tied to methods. I'm emotionally attached to making my corals grow as fast as possible, will do whatever it takes to get there.