Im wanting to move away from carbon dosing. Is a algea reactor as effective?
Carbon dosing vs algea reactor
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RedReefer
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So I run the octo reactor with chaeto. It grows like crazy. Every 10 -14 days I get over a half 5 gal bucket total. I keep a large hand full to re -seed the reactor. I'm running 100 gal total volume. I light the reactor opposite my display lighting. About 13 hours nightly.
jackson6745
Valuable Member
Not sure about a reactor, but I put an ice cap medium scrubber on my 300g system and it dropped the nutrient level substantially. I would have to dose a high level of carbon source to get that reduction and probably get slime or weird bacterial growth.
jackson6745
Valuable Member
Do you run skimmerless with that?
OP
OP
How well does it control nutrients compared to carbon dosing?
OP
OP
What do you nutrients run at?
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This is related..
Many people have trouble using carbon, and try adding on a scrubber to fix it. It's better however if you just start with scrubber-only if you want scrubber-only. If you want low nutrients, it depends on how good you build and run your scrubber, and if you have other filters. Any type of scrubber can get numbers to "zero" on regular test kits once the tank has cycled, if that is your goal. Algae is algae, and photosynthesis is photosynthesis. There just has to be enough of it at all times. Photosynthesis = Light x area x attachment x air/water interface turbulence.
If that is your goal, and if there are no other filters or water changes, then you'll want multiple scrubbers so that at least one is always filtering when you clean the other. When algae is the only filter, nutrients shoot up real quick when the filter stops.
Adding carbon changes the control of what gets the low numbers. The carbon will usually win if run strong enough, and will really slow down the algae. So they sort of fight each other. Same with GFO. The only carbon that gets into real reef water is from algae (glucose), so real reef water does not have to deal with extra carbon being added. All the filtering there is done by photosynthesis. Here is a comparison of algae scrubbers to carbon dosing (vodka, pellets, etc)...
Carbon dosing does not:
Remove metals.
Increase pH (dosing actually decreases).
Increase oxygen (dosing actually uses oxygen).
Remove CO2 (dosing actually adds CO2).
Work well without a skimmer.
Grow pods.
Provide any reverse photo-period pH stabilization.
Which of course means that scrubbers:
Remove metals, including copper and heavy metals.
Increase pH, usually by 0.1 or 0.2 pH per scrubber.
Increase oxygen directly by photosynthesis, and indirectly by bubbles or flowing water.
Remove CO2.
Do not require a skimmer, doser, or anything other equipment (an upflow version does not even need a water pump).
Grows tons of copepods (in saltwater), and even amphipods if you don't use freshwater to clean.
Can be set to reverse photo-period of the display.
Scrubbers also add trace elements (all organic traces in the ocean come from algae) including Vitamin C, Amino Acids, and Carbs (these come from algae in the ocean too).
Scrubbers also cannot over-dose, and they can't over-scrub. And if the scrubber is an upflow version, then it can't even dry out if the power goes out.
But probably the biggest advantage is that a tank can be set up to be scrubber-only, with no other equipment, and no water changes.
However let's not forget the fun part: You can take some of the algae from the scrubber and feed it your fish!
Many people have trouble using carbon, and try adding on a scrubber to fix it. It's better however if you just start with scrubber-only if you want scrubber-only. If you want low nutrients, it depends on how good you build and run your scrubber, and if you have other filters. Any type of scrubber can get numbers to "zero" on regular test kits once the tank has cycled, if that is your goal. Algae is algae, and photosynthesis is photosynthesis. There just has to be enough of it at all times. Photosynthesis = Light x area x attachment x air/water interface turbulence.
If that is your goal, and if there are no other filters or water changes, then you'll want multiple scrubbers so that at least one is always filtering when you clean the other. When algae is the only filter, nutrients shoot up real quick when the filter stops.
Adding carbon changes the control of what gets the low numbers. The carbon will usually win if run strong enough, and will really slow down the algae. So they sort of fight each other. Same with GFO. The only carbon that gets into real reef water is from algae (glucose), so real reef water does not have to deal with extra carbon being added. All the filtering there is done by photosynthesis. Here is a comparison of algae scrubbers to carbon dosing (vodka, pellets, etc)...
Carbon dosing does not:
Remove metals.
Increase pH (dosing actually decreases).
Increase oxygen (dosing actually uses oxygen).
Remove CO2 (dosing actually adds CO2).
Work well without a skimmer.
Grow pods.
Provide any reverse photo-period pH stabilization.
Which of course means that scrubbers:
Remove metals, including copper and heavy metals.
Increase pH, usually by 0.1 or 0.2 pH per scrubber.
Increase oxygen directly by photosynthesis, and indirectly by bubbles or flowing water.
Remove CO2.
Do not require a skimmer, doser, or anything other equipment (an upflow version does not even need a water pump).
Grows tons of copepods (in saltwater), and even amphipods if you don't use freshwater to clean.
Can be set to reverse photo-period of the display.
Scrubbers also add trace elements (all organic traces in the ocean come from algae) including Vitamin C, Amino Acids, and Carbs (these come from algae in the ocean too).
Scrubbers also cannot over-dose, and they can't over-scrub. And if the scrubber is an upflow version, then it can't even dry out if the power goes out.
But probably the biggest advantage is that a tank can be set up to be scrubber-only, with no other equipment, and no water changes.
However let's not forget the fun part: You can take some of the algae from the scrubber and feed it your fish!
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People have problems with both methods. Imo, nothing is more effective or easy/ maintenance free than carbon dosing. There is no reasonable limit to capacity and no weekly maintenence, etc.
True some people have issue "getting bacteria to work", But some have problem with the ats also. In both cases, I believe it comes down to time. You can't want magic in a couple weeks- sometimes things takes longer than that.
True some people have issue "getting bacteria to work", But some have problem with the ats also. In both cases, I believe it comes down to time. You can't want magic in a couple weeks- sometimes things takes longer than that.
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Carbon dosing
Adds oxygen from skimmer
Increases pH if skimmer has CO2 scrubber (0.2 to 0.4 pH units)
Carbon dosing increases heterotrophic bacteria which are food for corals and filter feeders
Unlikely to over strip nutrients from water
Over-dosing carbon is not an issue if you start low and ramp up over time
The feeding of corals is the big win in my book as they provide a means of delivering phosphate to corals.
I’m not knocking algae scrubbers but I think some of the criticism of carbon dosing is overblown.
Adds oxygen from skimmer
Increases pH if skimmer has CO2 scrubber (0.2 to 0.4 pH units)
Carbon dosing increases heterotrophic bacteria which are food for corals and filter feeders
Unlikely to over strip nutrients from water
Over-dosing carbon is not an issue if you start low and ramp up over time
The feeding of corals is the big win in my book as they provide a means of delivering phosphate to corals.
I’m not knocking algae scrubbers but I think some of the criticism of carbon dosing is overblown.
OP
OP
I have had good results with carbon dosing. In a heavily stocked 150 and feeding 3 times a day my nitrates hardly ever exceed 10 ppm. But Im dosing 200 mls of vodka a day. Plus the slime that covers everything in my sump can be a hassle. Plus it doesn't take very long for the gfo and carbon to become plugged up with the bacteria. So much that the gfo hardly gets time to work. My phosphate is consistently running around .2-.28. I ordered a algea reactor rated for 200 gallons. If it can keep the phosphate down to .1 or under I'll consider that a win.
OP
OP
Nothing to speak of yet. Im having a hard time getting chaeto to grow. Im up to 300mls of vinegar right now to keep nitrates below 20. The skimmer is needing dumped every other day so the carbon is doing its job.
OP
OP
Carbon dosing wont lower phosphate. Try running some Rowaphos in a reactor.
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