I have an issue with some hair and other algae. Because of this, my phosphate reading (Hannah) is 0 and my nitrate reading (Red Sea Pro) is also 0. Since the algae is consuming the nitrate and phosphate, what benefit does doing a water change have on my algae problem? My readings are 0 so I am not removing any phosphate or nitrate. It seems like I need to "unlock" the phosphate and nitrate before I can remove them with water changes. I don't see how water changes will solve my algae problem.
Algae Issue and Water Change Question
- Thread starter ddrueckh
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Randy Holmes-Farley
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Water changes are not typically a good way to deal with algae and nutrient issues, so you are correct in not seeing it as being especially useful.
To deal with algae via nutrients, you need to intercept the nutrients coming from the food before the algae gets it. While the readings are "zero", there are still plenty of nutrients int he water. There are many ways to go after them (such as organic carbon dosing, phosphate binders, denitrators, more skimming, etc.).
Biological control usually is a big help, such as fish that eats it, snails, etc.
And manual removal also helps considerably.
Thanks Randy. I have figured out that once you hit the major algae outbreak stage, the algae simply out competes any water changes and GFO. What I mean by this is the algae absorbs the phosphate and nutrients too fast, not giving the GFO reactor enough time to absorb the phosphate. I believe that you need to do two things to get rid of a bad algae problem.
1. Pull out and throw away as much algae as you can (exports the phosphate)
2. Get a clean up crew (snails, crabs and urchin) to remove what you can't pull out. They will eat the algae and release (poop) the phosphate back into the water column so it can be removed with water changes and/or by running GFO.
I noticed that when I added a decent clean up crew, my phosphate went from 0 to .08. It had stayed at 0 for months prior to adding the clean up crew.
From my experience, using GFO will not kill algae in a tank with a bad algae problem. I ran 2 cups of BRS High Capacity GFO changed every 2 weeks in a 60 cube for months. I didn't notice any reduction in my algae. I was only feeding one cube of food every 3 days. I believe I was just throwing out and replacing good GFO during that time. The algae absorbed the phosphate too fast. Being that GFO reactors have a low flow, there wasn't enough time for the water to flow through the reactor so the media could remove the phosphate. I use RO/DI water and am certain that my water has 0 TDS. My water change saltwater has 0 phosphates and 0 nitrates. I have checked this multiple times with different test kits/meters. I believe my phosphate issue is from my live rock.
1. Pull out and throw away as much algae as you can (exports the phosphate)
2. Get a clean up crew (snails, crabs and urchin) to remove what you can't pull out. They will eat the algae and release (poop) the phosphate back into the water column so it can be removed with water changes and/or by running GFO.
I noticed that when I added a decent clean up crew, my phosphate went from 0 to .08. It had stayed at 0 for months prior to adding the clean up crew.
From my experience, using GFO will not kill algae in a tank with a bad algae problem. I ran 2 cups of BRS High Capacity GFO changed every 2 weeks in a 60 cube for months. I didn't notice any reduction in my algae. I was only feeding one cube of food every 3 days. I believe I was just throwing out and replacing good GFO during that time. The algae absorbed the phosphate too fast. Being that GFO reactors have a low flow, there wasn't enough time for the water to flow through the reactor so the media could remove the phosphate. I use RO/DI water and am certain that my water has 0 TDS. My water change saltwater has 0 phosphates and 0 nitrates. I have checked this multiple times with different test kits/meters. I believe my phosphate issue is from my live rock.
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