GFO a good or bad idea?

[Purpletang92]

Have you guys noticed any ill effects using GFO even in small quantities in your reef tank? My lps shrink a lot whenever I use it no matter what.

 

[PopBot16]

What is your PO4 before and after? And how quickly does it get there?

 

[landlubber]

truthfully it's both.
GFO is incredibly effective at pulling phosphate from the water. If you use too much it will strip more than you might want and sets the user up for bigger issues like dinos.
Use it if needed (ideally in a reactor) but just be cautious not to use too much or run in without testing frequently to stay on top of your numbers

 

[bobnicaragua]

I have 2 bags in my sump of GFO and carbon. One bag gets changed every 2 weeks. No issues here, but running passively in a bag is a less effective/gentle way to do it.

 

[Aquariumaddictuk]

I only managed to control po4 "gently" with GFO when I started adding a little to filter socks & changing little & often.in a reactor it was too aggressive & caused cyano.

 

[rtparty]

I don't see any reason to run it. Phosphate isn't nearly as bad as so many preached for years

 

[Purpletang92]

What is your PO4 before and after? And how quickly does it get there?

It was .04 I just put a little in only because the glass was getting a green film, nothing died but I just noticed hammers are not as open. I have pulled it and will continue to monitor.

 

[Purpletang92]

I have 2 bags in my sump of GFO and carbon. One bag gets changed every 2 weeks. No issues here, but running passively in a bag is a less effective/gentle way to do it.

I’ve noticed if I use too much carbon I kind of get the same effect, have you noticed this before?

 

[Pistondog]

It was .04 I just put a little in only because the glass was getting a green film, nothing died but I just noticed hammers are not as open. I have pulled it and will continue to monitor.

As you found, reducing nutrients is not an effective way to control algae.
At 0.04 ppm po4, you risk starving your corals.

 

[Purpletang92]

As you found, reducing nutrients is not an effective way to control algae.
At 0.04 ppm po4, you risk starving your corals.

Figured that’s what happened but I’ll continue to monitor and won’t change anything else.

 

[landlubber]

yea no way i'm using GFO for .04. I'd just feed a bit less if its bothering you

 

[Purpletang92]

yea no way i'm using GFO for .04. I'd just feed a bit less if its bothering you

This is that “tinkering” thing that they talk about in this hobby, lol I leave things alone.

 

[exnisstech]

It was .04 I just put a little in only because the glass was getting a green film, nothing died but I just noticed hammers are not as open. I have pulled it and will continue to monitor.

I've been told film on the glass was a good thing and normal for healthy tanks and is just part of reefing . I have a tank with PO4 0.2-0.35 and another with PO4 that stays around 0.02-0.04 and I have to clean the glass every few days on both. I also have sponges and other cool stuff growing on rocks in the shaded areas.

 

[Purpletang92]

I've been told film on the glass was a good thing and normal for healthy tanks and is just part of reefing . I have a tank with PO4 0.2-0.35 and another with PO4 that stays around 0.02-0.04 and I have to clean the glass every few days on both. I also have sponges and other cool stuff growing on rocks in the shaded areas.

Do you feed phytoplankton ?

 

[exnisstech]

Do you feed phytoplankton ?

No I never have.

 

[Purpletang92]

No I never have.

What about the foods you feed ? Frozen? Pellets?

 

[JayM]

I don't see any reason to run it. Phosphate isn't nearly as bad as so many preached for years

My LPS corals disagree. They were looking very unhappy in the high .1x range. Got it down to .05 +/- and they are back to looking great.

 

[rtparty]

My LPS corals disagree. They were looking very unhappy in the high .1x range. Got it down to .05 +/- and they are back to looking great.

I ran around .4ppm on my PO4 for a long time. None of my LPS cared one bit. Tough to get a sense but the hammers and frogspawn all had well over 100 heads on them. They were pushing 200+. This picture was taken with NO3 around 10ppm and .2ppm PO4. PO4 started dropping from the .4 when I started dosing ammonium bicarbonate.

 

[exnisstech]

What about the foods you feed ? Frozen? Pellets?

Normally frozen is PE mysis, and rods original. Pellets formula one and two pellets, sustainable aquatics pellets, and dk1 pellets. I add selcon, vitachem and reef roids mixed in with the food 2-3 times a week. I mix the pellets with the frozen. I have some large fish and do feed heavily. I don't remember ever not having to clean the glass at least twice a week on any tank if had over the last 8+ years. I'm far from a neat freak too.

 

[Purpletang92]

I ran around .4ppm on my PO4 for a long time. None of my LPS cared one bit. Tough to get a sense but the hammers and frogspawn all had well over 100 heads on them. They were pushing 200+. This picture was taken with NO3 around 10ppm and .2ppm PO4. PO4 started dropping from the .4 when I started dosing ammonium bicarbonate.

Your system seems to have very high light, correct me if I’m wrong but, you can run high nutrient with high lighting ? Lower nutrient means lower lighting? I read something somewhere about this.