Carbon dosing advice

[punchy7080]

Tank is about nine months old. Just a couple months ago my nutrients bottomed out and I got cyano. Dosed chemiclean and all good. Dosed NeoPhos for a few days to bring levels up. Fast forward to beginning of August, no3 at about 40 and po4 at .74. Just a little bit of brownish green algae on the rocks but coral and coralline growth had really slowed. Had some nopox so started with that and levels slowly started coming down. Made my own diy with vinegar, vodka, ro/di. Currently dosing 50ml/day on about 300 total gallons. Also did a 20% water change about 10 days ago. Using phosgard and phosphate-e to help as well. Nitrates are 19.9 and phosphate is .19. Problem and question is, rocks are mostly covered with a very short brown/green hair algae. I need to dose even more to get nutrients down a bit. Do I stay the course or pull back and get po4 down with gfo and do water changes for no3? Corals all look fine so I’m not panicking and happy to stay the course if that’s best. Thanks!

 

[wculver]

I've tried doing this in the past but I felt I kept chasing numbers and could never get the additive level right long term. The change I made was adding a carbon reactor which is much more regular about waste processing and IMO not as aggressive as something like NoPox.

At this point with about 250 gallons of volume I run 1 cup of pellets and from time to time GFO as Phosphate rises above around .08 PPM with a goal of .03 PPM going for the most stability as possible in the process.

So my suggestion would be to run the GFO as you suggested and consider a carbon reactor for the Nitrate and long term processing.

 

[punchy7080]

I've tried doing this in the past but I felt I kept chasing numbers and could never get the additive level right long term. The change I made was adding a carbon reactor which is much more regular about waste processing and IMO not as aggressive as something like NoPox.

At this point with about 250 gallons of volume I run 1 cup of pellets and from time to time GFO as Phosphate rises above around .08 PPM with a goal of .03 PPM going for the most stability as possible in the process.

So my suggestion would be to run the GFO as you suggested and consider a carbon reactor for the Nitrate and long term processing.

Thanks for the response. I have two concerns. Maintaining proper nutrients but also not growing the algae lol. Are bio pellets less likely to encourage algae growth while lowering nitrates and phosphates?

 

[wculver]

Thanks for the response. I have two concerns. Maintaining proper nutrients but also not growing the algae lol. Are bio pellets less likely to encourage algae growth while lowering nitrates and phosphates?

They don't do anything for the algae directly but they do directly help Nitrates and secondarily Phosphates which in turn indirectly lowers the tendency for algae to grow. Lowering nutrients is the key to algae control.

That said, I still have to add provisional GFO every few months for phosphate removal. I typically feed the coral and clams daily and the food I use does increase phosphate over time higher than the carbon dosing reactor manages on its own. If it were just the fish with shrimp/pellets/nori I wouldn't have to.