Dry rock & GFO

[WestMI-Reefer]

New system (6 weeks old)
Dry rock, a few live rocks to seed the system
Inhabitants: clownfish pair

I had phosphates climb to 0.5. This seems like a normal problem to have starting with dry rock.

i dosed GFO at the recommended level in a bag in the sump. I noticed ph drop slightly.

Phosphate was reduced to 0.07 later that day
I was shocked at the effects of GFO and wanted to share that experience.

I pulled the GFO bag and performed a 20% water change.

Todays test’s looked good

 

[KrisReef]

You might want to remeasure phosphate level tomorrow to see if you measure phosphate leaching from the dry rock?
Yes, GFO can drop levels very quickly.

 

[WestMI-Reefer]

You might want to remeasure phosphate level tomorrow to see if you measure phosphate leaching from the dry rock?
Yes, GFO can drop levels very quickly.

I tested again and it dropped from 0.02 to 0.00 with no GFO. I fully expect the rock to continue to leaching phosphate. This can take months, right? Hopefully if I keep it in check with GFO now, the inevitable “ugly phase” will be much more manageable.
I have to be more careful not to let GFO bring levels to 0 again. I couldn’t believe how quick and effective it was, I’ll back off the dose if it’s needed again because it worked too well for me.

 

[KrisReef]

I tested again and it dropped from 0.02 to 0.00 with no GFO. I fully expect the rock to continue to leaching phosphate. This can take months, right? Hopefully if I keep it in check with GFO now, the inevitable “ugly phase” will be much more manageable.
I have to be more careful not to let GFO bring levels to 0 again. I couldn’t believe how quick and effective it was, I’ll back off the dose if it’s needed again because it worked too well for me.

It may have worked too well if it remains at zero? You may need to feed heavy or add trace phosphate if it’s stuck at zero.

Always double check the numbers before changing directions! Hopefully the tank will be thriving going forward

 

[WestMI-Reefer]

It may have worked too well if it remains at zero? You may need to feed heavy or add trace phosphate if it’s stuck at zero.

Always double check the numbers before changing directions! Hopefully the tank will be thriving going forward

I pulled the bag at 0.02 so maybe the skimmer thats still breaking in (no collection) got the rest? I realized I messed up 3 months ago when I ordered the Hl713 phosphate (ppm) which measures high range with +/-0.05 ppm tolerance. I just ordered the hanna phosphorus ULR Hl736 which measures low ranges with more precision. That will reveal if its truly bottomed out. Silly and unnecessarily expensive newcomer mistake lol

 

[KrisReef]

I pulled the bag at 0.02 so maybe the skimmer thats still breaking in (no collection) got the rest? I realized I messed up 3 months ago when I ordered the Hl713 phosphate (ppm) which measures high range with +/-0.05 ppm tolerance. I just ordered the hanna phosphorus ULR Hl736 which measures low ranges with more precision. That will reveal if its truly bottomed out. Silly and unnecessarily expensive newcomer mistake lol

I don't believe a skimmer would lower dissolved minerals, but the error margin between the two meters is definitely a factor here, ime. I had the old meter before i got the ULR. I got that before they came out with the ULR that reports in ppm, so I always have to figure out what the ppb translates into.

I've had better luck with that meter since I've started using a 10mm syringe to collect the sample and store the cuvette in RODI between uses. Lots of tricks to be learned here on Reef2Reef! Sadly, I keep repeating some mistakes, part of getting old I guess.