Can't decide between GFO and Biopellets.....

[Harrison Gordon]

So I have had a reactor for almost 6 months now, the first half I ran biopellets and didn't see any results and since then I've been running GFO.

I don't think I tried the biopellets correctly (didn't use enough, enough flow) and it was ineffective. After my LFS said to switch to GFO I modified the reactor to accommodate the new media.

I have watched so many videos and looked through so many forums I can't make up my mind--I just want to hear from real people.
What do you prefer? Do you use both together, one, or the other? What other types of filtration do you use?
I have always and still have an algae problem, trying to figure out is it the lights or the nutrients or both? N 5 to 10 depending on the day; P near 0 to 0.03

My BIG question is how GFO is for Po4 and pellets are for No3, and yet people seem to only use one or the other while having both nutrients near 0. Could someone please explain this or give personal experience?

Thanks so much!

 

[jda]

You are on the money - GFO and Organic Carbon do not do the same thing. Biopellets can help lower your N, but don't do as much with P - they can lower P, but more like a side effect than a direct effect. LC, GFO or even Aluminum Oxide (Phosguard) are just for P. I would not sweat P from 0 to .03. I would get the N down if you want to do anything.

First, figure out why you have algae. Your probably have a surplus of N and/or P that the algae is soaking up. Is it from dry/dead rock or live rock that was neglected and is releasing P that the algae can grab in proximity before it makes it to the water column? Is this an old tank where the levels have built up a bit over time? Is it a new tank (less than a year) where it might not be good at lowering N on it's own yet? I would tailor your solution based on the root problem.

 

[Harrison Gordon]

Thanks jda!
It's a new tank, ~8mo. The live rock is some that my LFS cured and some that is imported from Fiji or something like that.
I've been getting Cyano on the sanded, some really annoying encrusting algae that can only be scraped off the glass with fingernail or blade (won't come off of rocks), and your average green slimy glass algae.

It's just....my params are pretty low, but I'm getting moderate algae growth with less than 8hr photoperiod with just two (new) T5 bulbs (the other four are good if I want to farm micro algae )

I didn't realize how fast it was growing til today; last night I had siphoned the sanded because the cyano was getting thick enough to convince me to get my hands wet, and halfway through the photoperiod there is already a brand new thin layer on the bed.

Gonna order new powerhead because obviously flow is an issue w/cyano, but sidenote wherever my powerhead are directed the encrusting algae grows like crazy. For this it definitely seems like the issue is not as much light but more so nutrients: just gotta figure out where they're coming from I guess!

 

[jda]

I would not sweat such a young tank. If you have sand, it will eventually develop anoxic areas (rock also) that will process nitrate down to near-zero... but this takes time. If you are bare bottom, then this can be tougher. You can inhibit this natural part of the cycle by running GFO or organic carbon by keeping resources from those developing bacteria - you might have to pay this back on the back end.

You most likely have more N and P available than you can read with the test kit - they are just bound up in the cyano and stuff. Availability is not always easy to measure...

Cyano, dinos, etc. are a rite of passage in newer tanks. Nobody likes it or wants to hear it, but the best thing might just be to let the tank ride and have nature develop the anoxic areas to process the No3 into N gas. It sucks... no denying that. I have a new tank that I set up in Feb and it had all kinds of cyano and algae until about July, but I let it be and it has turned the corner now and is processing N on it's own and the algae is all gone.

 

[Harrison Gordon]

Cool. But you say I am inhibiting the bacteria?

Anyways yeah I guess I know that new tanks always go through algae, but late spring I got this stubborn hair algae that spread over all the rocks and my LFS said don't even try, just replace your live rock and start GFO. So....I'm trying to avoid stuff like that from happening again.

I added some more GFO today and hopefully I see improvement over the next few weeks. Then I either buy more or switch to biopellets and give them another run; after all the first time didn't really count.

 

[jda]

If you are feeding bacteria in the water column with organic carbon, then you can starve them of building blocks in the rocks and sand... or at least you could be once they levels get kinda low. This is probably enough to go around if the N is at 100, but for tanks with less than 20, they never seem to develop the ability to handle N on their own when people dose organic carbon.