So you were told your rock leaches phosphates? NOT!

NanaReefer · Feb 3, 2015

This has been bugging me for quite some time. One of the biggest reasons given around the forums for algae issues has been, your rock is leaching phosphates.
If this is so, than why have I (and so many others) never experienced this phenomenon? 5yrs and I've only used BRS Reef Saver and Dry Pukani. No algae issue, not even a hint of HA.
So I've been on a quest to find the truth to what I've always believed to be one of those rumors spread to explain the mystery.
The way I interpret this article may be different from others.
Thank you Randy Holmes-Farley
Phosphate and the Reef Aquarium by Randy Holmes-Farley - Reefkeeping.com

d2mini · Feb 3, 2015

Not sure what you are referencing in the article.
But even the last paragraph says...

Problems involving phosphorus and subsequent algae growth can be among the most difficult to solve in a reef aquarium, especially if the live rock and sand have been exposed to very high phosphate levels, after which they may be acting as a phosphate reservoir.

Phishy McGee · Feb 3, 2015

I bought used live rock from an old tank. I set up the tank with 125 gallons of RO water and turned the pumps on. I took a phosphate ready 3 days in and it was through the roof, like off the scale that the test can do. I hadn't added a speck of food, a fish, coral, nothing but old rock and water. Rock can leach phosphates for sure. I set up a phosphate reactor and have been running one ever since...

NanaReefer · Feb 3, 2015

Read the article in its entirety. Don't just quote what you find agreeable to your belief.
If in fact the "leaching phosphate" from the rock was the cause of said algae, than why isn't everyone with rock in their tanks experiencing it?

d2mini · Feb 3, 2015

NanaReefer said:
Read the article in its entirety. In order for the phosphate to be released from aragonite a chemical reaction must exist first. Don't just quote what suits your opinion.

It's not my opinion so no need to get snotty about it.
But most of that article is beyond some people's comprehension so if you are trying to make a point, you'd be doing yourself a favor to just post the relevant info here and/or paraphrase.
But typically the final paragraph will sum up the rest of the article.
My point is that even Randy says there "may" be stored up phosphate in the rock that is being released, regardless of what's causing it to be released.

I'm also not sure why you brought up your 5yo rock like it's supposed to mean something?
If you have good husbandry, your rock should last you a lifetime with no issues. This doesn't prove a thing one way or the other.
No one ever said that any rock, live or dry, will eventually start releasing phosphate. Well, if they did, they shouldn't have.

Is it the cause of HA in someones tank? Who knows? Could be. Could not be.
I would look at the history of the rock first and foremost (craigslist find?) and go from there with things like tank history, feeding, etc.

Remember, there are no absolutes in this hobby.

NanaReefer · Feb 3, 2015

I'm not being snotty as you so eloquently put it. I said nothing about 5yr old rock. No absolutes for sure and all about interpretation.

Trex · Feb 3, 2015

NanaReefer said:
Read the article in its entirety. Don't just quote what you find agreeable to your belief.
If in fact the "leaching phosphate" from the rock was the cause of said algae, than why isn't everyone with rock in their tanks experiencing it?

That wouldn't be the ONLY cause of algae, there are others.

Not everyone's rock is the same, and not everyone's tank is the same, and not everyone's source water is the same, and not everyone's maintenance schedule is the same.......

Dcmatranga · Feb 3, 2015

I should just put this out there and say - I'M OPINIONATED, lol - all of us aquarists are - we all know that. That said, interesting point. I myself started with BRS dry Fiji, no phosphate problems whatsoever - but, that's just my particular case. Phosphates can come from many different places, and there are two main kinds - ortho and organic, I believe our test kits only read one of those (If Randy can chime in, he may have additional input, he's the man).

5 year old rock purchased on craiglist is tough to evaluate - we don't know how long the system it was in was neglected, therefore the phosphate leach would be unable to be determined as there's no way to really measure how much phosphate is in the rock and how long it will leach out for. If you have an algae issue, chances are your phosphates will read low or zero as the algae is consuming it.

One good post here, is that everyone's chemistry, tank Maintenence, water is all different. A buddy of mine had a bad phosphate issue, could not find the root. Ended up testing the output of fresh ro/di and there was a reading, made a fresh batch of salt and the problem compounded - so where were the phosphates coming from, he was adding them himself. Don't rule out testing a new batch of saltwater or ro/di - often those are the last steps to troubleshoot and could be the issue.

bobstir · Feb 3, 2015

OP, the common consensus is not that ALL rocks leak phosphate, rather, SOME rocks may leak phosphate if they have been in a phosphate saturated system and/or contain dead biological matter. In fact, when rocks do leak phosphate, there are usually tell-tale signs that they are doing so (algae growing on them, especially at the tips).

kevantheman35 · Feb 4, 2015

Most dry rock definitely leaches phosphates until depleted. I have observed this while curing new dry rock. I have to place the dry rock in a bin with steong flow and continuously change the water until the high phosphate levels cease. You can clearly see this if you do a simple test by placing a small amount of dry rock in a jar for a few days and test the water. Here is a similar experiment done by Reefdvms on youtube. In my experience however it takes much longer than a few days to see results.

http://youtu.be/4Vkn4vL1qRg

Zacco · Feb 4, 2015

Rock can bind up phosphates and release them over time. Yes some rock can be phosphate free and some not. Main concern is what it stuck to the surface and in the pores if the rock. Dried organic matter, dirt, ext. All rock should be cured to loosen and export these said things before introducing it into your tank. I started curing 80 pounds of BRS Reef Saver Rock this past Saturday in a tub of RO/DI Salt Water. I will post my Phosphate Readings this weekend. This will give the rock a week of soaking before testing with a Hanna Checker.

Zacco · Feb 4, 2015

Soaking your rock for one or two days and then checking for phosphates is simply not enough time. This is why it is recommended that you cook/cure your rock for 4 to 6 weeks.

Randy Holmes-Farley · Feb 4, 2015

I would suggest that there are three types of rock that can release phosphate over time, and, of course, many that do not:

1. Rock that has dead organic matter on it (like dead algae/sponges/etc.), no matter how old or where it came from. The organics will break down and release some phosphate. Bleach might be the best way to treat this rock, followed by some way to remove the inorganic phosphate that may result (like rinsing in low phosphate water).

2. Rock that, even if once pristine, was exposed to higher than desirable inorganic phosphate concentrations at the end of its time in an aquarium. This will be inorganic phosphate bound to the calcium carbonate surfaces, and will be somewhat easier to get rid of than the organic matter in 1. Keeping the rock in low phosphate water long enough will work, as can dissolving away the outside in acid.

3. Mined rock that has been exposed to terrestrial phosphate in runoff may have a lot of phosphate permeating it. An acid treatment might not be optimal for this as the phosphate may also be deeper inside of it, and treatment in low phosphate water for an extended period might be best.

Gopi · Feb 4, 2015

My rocks have been cooking since early December. My previous test kit didn't read low enough. With my new Hanna checker, the water after one week read 0.12 while new rodi salt water was 0.00. I'm not feeding the container so phosphate must be coming from the rock. (I had also gone the Craigslist route...mix of those with LFS rocks...and it was definitely the Craigslist rocks with the algae issues.)

Zacco · Feb 4, 2015

I would also like to interject that i gave the 80 pounds of BRS Reef Saver Rock a 5 hour straight Vinegar Bath. You can see what the mild acid pulled from the pores of the rock. The tub sides had dirt, little bits of algea and other dried organic matter stuck to it along with a 1/4 inch if sediment on the bottom of the container. Yes ,some if this sediment was calcium dust. No argument there.

beaslbob · Feb 4, 2015

One thing I'm sure of rock and everything else in a newly setup tank can leach or at least contain many many things. But those things are temporary.
what is more important is the long term effects of the bioload you're maintaining.
So we get initial silicates and an initial bloom of diatoms. But those silicates are temporary because they are not being added by the bioload.
So I think we should not worry about phosphates coming from non bioload temporary things.
And setup a balanced eco system that consume those things.
And, of course, operate the tank to discourage diatoms, algaes, cyano and so on.
As result we wind up with a long term, stable, and balanced environment that depends on the biological balance not chemicals, mechanicals and so on.
my .02

NanaReefer · Feb 4, 2015

Great info here! I'll admit I started this thread out of pure frustration. Sick of reading post about DO NOT BUY BRS ROCK because it leaches phosphates. Yet I personally never experienced this issue myself.
I Humbly accept the fact that although I may not have, others could have. Now I don't even know what I was trying to accomplish. But I've definitely been schooled

macscale · Feb 4, 2015

NanaReefer said:
Great info here! I'll admit I started this thread out of pure frustration. Sick of reading post about DO NOT BUY BRS ROCK because it leaches phosphates. Yet I personally never experienced this issue myself.
I Humbly accept the fact that although I may not have, others could have. Now I don't even know what I was trying to accomplish. But I've definitely been schooled

OH dont be harsh on yourself!
Repeats in the hobby forums are pretty common!

saltyphish · Feb 4, 2015

I believe the difference is the rock leeching the excess nutrients has soaked in water with high nitrates and phosphates which is why it leeches the nutrients back, The tanks you are using for examples of not having algae issues is correct in the fact that the rocks are not leeching nutrients back into the water but the difference is those rocks were probably never in a high nutrient tank to allow them to soak the nutrients.

NanaReefer said:
Read the article in its entirety. Don't just quote what you find agreeable to your belief.
If in fact the "leaching phosphate" from the rock was the cause of said algae, than why isn't everyone with rock in their tanks experiencing it?