Shutting white lights to starve Green Hair Algae?

[wolffman1992]

I started running gfo by using half of the recomended dose, observed my corals and saw no ill effects. A week later I increased the amount to the full recomended dose. While using gfo I recommend observing your corals as to see if anything bad is happening but as previously stated I find it extremely safe. Here are some pictures of my tank

http://s578.photobucket.com/user/Wolff1992/slideshow/fish tank update

 

[cilyjr]

There are different types of gfo with different absorption rates. Gfo will up take phosphate slowly..... Gfo is meant to bring down levels slowly.

I recently added 1 cup of GFO to my 220 total system gallon to bring PO4 down from .07 I was shooting for .03. I checked the next day using hanna phosphorus ulr meter then using math to get the PO4 number. It was at .02 (I do 3 checks in a row to account for margin of error. Every time).

I thought wow I can't believe that just 1 cup could remove that much PO4 that fast. But Randy Holmes-Farley and others chimed in on my post on reef2reef saying quite the opposite of what you are suggesting; that GFO will strip PO4 very quickly. And can saturate within hours.

Link to the thread
http://www.reef2reef.com/threads/po4-drop.240587/

 

[wolffman1992]

Did you notice any ill effects from the drop?

 

[wolffman1992]

also what type wand brand were you using? Also flow rate has a lot to do with it.

 

[cilyjr]

No I pulled it out quickly. I'm not against the use of gfo as a rule. But I had an STN event a few years ago that I anecdotally attribute to gfo depletion of PO4. As I said it's purely anecdotal so I now only add a small amount for a day or 2. And test all the time when I have it.

Again I'm not saying don't use it. I am saying don't drop ANYTHING in your tank before testing for what you are trying to add/remove ect

 

[cilyjr]

Brs generic Gfo. As stated I placed in an upflow reactor which is run off a manifold. I'm sure I have a very effective way to run it.

 

[wolffman1992]

I use Brs too. I mean while it seems like a big drop randy stated it would increase back up to the level it was previously at if you removed the gfo. Did your corals react negatively ?

 

[cilyjr]

of course it would rise if i remove it(( and not do anything else about it) i mean we are all dumping in po4 in our tanks anytime we feed. i attribute my rise in po4 to after i scrape my turf algae scrubber. seems to happen every time now. so for me gfo is a band aid when i scrape the scrubber for a day or so. my po4 sits at about .02 to .04 on average.

my original post was to dispute the speed at which GFO will remove po4. not that it will kill everything in a marine aquarium.

 

[wolffman1992]

of course it would rise if i remove it(( and not do anything else about it) i mean we are all dumping in po4 in our tanks anytime we feed. i attribute my rise in po4 to after i scrape my turf algae scrubber. seems to happen every time now. so for me gfo is a band aid when i scrape the scrubber for a day or so. my po4 sits at about .02 to .04 on average.

my original post was to dispute the speed at which GFO will remove po4. not that it will kill everything in a marine aquarium.

Ok I respectfully admit I may have been wrong about gfo slowly decreasing phosphates. However logically speaking if your po4 will rise after the removal of gfo and we are always adding po4 to the water column, as long as you keep feeding and have algae dying off and in turn releasing nutrients back into the water it is safe to say po4 will not remove all po4 present in the water in most cases. And to conclude can help cure an algae outbreak safely which was my over all point. But again I do admit I was wrong about the speed.

 

[cilyjr]

i hear ya. i just want people to be careful with anything they add. and test.

 

[JohnK]

Way back when GFO was pretty new to the hobby, and when I first tried it I used too much and ended up dropping the phosphate fast and IIRC in the process my alk took a dip. One way or another my system definitely felt some shock.

Whatever the case, there are multiple variables; what type of GFO, how much, what kind of flow rate through it, passive vs active flow, and how high the phosphate is to begin with.

I agree that nuisance algae(s) can often take up nutrients about as quickly as they are released/produced so that tests come back near zero but the algae still grows. Bottom line, algae growth is often a better indicator of nutrient levels than hobby grade test kits.

 

[delta]

Are you sure it hair algae and not byropsis?