Dealing with high nitrates and phosphates
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UK_Pete
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Edit: Weirdly I only saw the first few posts of this thread and hence posted stuff thats already been said. So edited this to remove irrelevant info.
I have a 55 too, and have dosed vodka for several years. It works excellently but I am going to convert to vinegar once this doser bottle runs out because its cheaper and easier to dose accurately. With a small tank using vodka you end up dosing such small amounts that it can be tricky to measure them. Using a doser pump, I found that I could not use silicone tube, because in the 24 hours between doses, the alcohol evaporated out of the tube (ethanol diffuses through silicone tube) enough that the next dose was undersized *. I had to buy a piece of teflon tubing to stop this.
1 ml per day is my maintenance dose. My nutrients were zero though and I had to dose nitrate and phosphate because vodka dosing while feeding very little resulted in zero nutes.
I would probably not go above 2 or 3 ml a day until you are comfortable with it all.
Carbon can deplete oxygen, especially at the start (day 2 or 3 often). What happens is that the carbon (IE vodka, vinegar) builds up in the tank, while there are too few bacteria to use it up. Then as the bacteria multiply, their numbers increase exponentially. So suddenly there are lots of bacteria, and plenty of carbon and nutrients, so the bacteria have a party. That uses lots of oxygen. The idea is to increase the carbon dosing so slowly at first, that your bacteria numbers reach a fairly high level slowly, rather than suddenly 'catching up' with the elevated quantity of carbon in the water. Then you can increase carbon faster once they have caught up. Its just to prevent that initial spike of oxygen consuming bacteria, which can stress fish if the oxygen levels fall too low. I think that its essential to step up your skimmer to overdrive so make sure you have plenty of CO2 release, and oxygen intake, to the tank. The spike, if you let it happen, can lower the pH too (because it also creates CO2). You can have some limewater on hand ready for this if you like. The spike is usually visible on day 2 or 3 as a haze in the water. Watching pH and dripping limewater if it drops more than say 0.3 pH units would be the way to do that. The limewater will remove the CO2.
You won't see much nutrient reduction till you are up to 1 ml a day at least, and with nutes that high, it might take a higher dose. Personally I think that with nutes that high, your sand bed is probably leaching quite a bit of nutes, carbon can deal with that, but it takes a higher dose. My opinion is that when you start dosing carbon, with a sand bed with lots of nutes in it, the sand bed will have to be slowly depleted of nutes over some months of carbon dosing. I got fed up with this process, and ended up removing the sand bed. In my case my nutes then dropped in a couple of weeks to very low (pretty much my target levels). I was going to put the sand bed back in after cleaning it but decided to go BB at that point and have stayed BB since then. If you do decide to remove and clean your sand, it might be possible to acid wash it, but I would ask Randy here about that if you do want to try it. I never did it but planned on doing it. That should remove nutes from the sand more effectively I thought (check though with Randy).
* basically I would set the thing up, dose 1 ml, then come back to it the next day just before the next dose, and nothing would come out of the tube. Investigating I found that the liquid in the tube had gone 'backwards' because I assume it diffuses through the silicone. When I replaced the silicone with teflon tube, 0.5 mm inside diameter, it worked fine.
I have a 55 too, and have dosed vodka for several years. It works excellently but I am going to convert to vinegar once this doser bottle runs out because its cheaper and easier to dose accurately. With a small tank using vodka you end up dosing such small amounts that it can be tricky to measure them. Using a doser pump, I found that I could not use silicone tube, because in the 24 hours between doses, the alcohol evaporated out of the tube (ethanol diffuses through silicone tube) enough that the next dose was undersized *. I had to buy a piece of teflon tubing to stop this.
1 ml per day is my maintenance dose. My nutrients were zero though and I had to dose nitrate and phosphate because vodka dosing while feeding very little resulted in zero nutes.
I would probably not go above 2 or 3 ml a day until you are comfortable with it all.
Carbon can deplete oxygen, especially at the start (day 2 or 3 often). What happens is that the carbon (IE vodka, vinegar) builds up in the tank, while there are too few bacteria to use it up. Then as the bacteria multiply, their numbers increase exponentially. So suddenly there are lots of bacteria, and plenty of carbon and nutrients, so the bacteria have a party. That uses lots of oxygen. The idea is to increase the carbon dosing so slowly at first, that your bacteria numbers reach a fairly high level slowly, rather than suddenly 'catching up' with the elevated quantity of carbon in the water. Then you can increase carbon faster once they have caught up. Its just to prevent that initial spike of oxygen consuming bacteria, which can stress fish if the oxygen levels fall too low. I think that its essential to step up your skimmer to overdrive so make sure you have plenty of CO2 release, and oxygen intake, to the tank. The spike, if you let it happen, can lower the pH too (because it also creates CO2). You can have some limewater on hand ready for this if you like. The spike is usually visible on day 2 or 3 as a haze in the water. Watching pH and dripping limewater if it drops more than say 0.3 pH units would be the way to do that. The limewater will remove the CO2.
You won't see much nutrient reduction till you are up to 1 ml a day at least, and with nutes that high, it might take a higher dose. Personally I think that with nutes that high, your sand bed is probably leaching quite a bit of nutes, carbon can deal with that, but it takes a higher dose. My opinion is that when you start dosing carbon, with a sand bed with lots of nutes in it, the sand bed will have to be slowly depleted of nutes over some months of carbon dosing. I got fed up with this process, and ended up removing the sand bed. In my case my nutes then dropped in a couple of weeks to very low (pretty much my target levels). I was going to put the sand bed back in after cleaning it but decided to go BB at that point and have stayed BB since then. If you do decide to remove and clean your sand, it might be possible to acid wash it, but I would ask Randy here about that if you do want to try it. I never did it but planned on doing it. That should remove nutes from the sand more effectively I thought (check though with Randy).
* basically I would set the thing up, dose 1 ml, then come back to it the next day just before the next dose, and nothing would come out of the tube. Investigating I found that the liquid in the tube had gone 'backwards' because I assume it diffuses through the silicone. When I replaced the silicone with teflon tube, 0.5 mm inside diameter, it worked fine.
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Randy Holmes-Farley
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Reef_a_holiks
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Is carbon dosing something you have to do forever, or can you stop when your nitrates are down to zero? I dont under stand why some can keep zero nitrates with the common filtration ( sump, macro algae, & skimmer) then some of us have to do carbon dosing, and bio pellets and stuff like that . Only reason Ide understand the extra work like carbon dosing would be if your tank is way over stocked or over fed. I am having nitrate problems as well, although mine dont pass 10ppm, I am not relying on carbon dosing or anything of that sort yet, I feel with my filtration, bio load and water changes, my nitrates should be at zero. Some thing is causing my nitrates that I have not figured out yet and before I go carbon dose, I will do a 100 percent water change and start new.NoPox, works fine, as do the DIY equivalents, vinegar and vodka.
IMO you shouldn't freak out and do an entire water change. Vodka dosing is amazing, as long as you read the article and follow the dosing chart. I had better luck with cheap vodka than with nopox, which had very little impact on phosphate. I liked the pretty photo on the NoPox box so I tried it and it wasn't nearly as effective as 80 proof vodka. I just put it in the sump every day around the am feeding. Good luck!
Serious API is a load of crap, im talking from experience. I also had nitrate issues, my API test kit put me in 50ppm range and i went mental.. I then did a test on my nano and same story. I immediately ordered 400L of water, then did 50% water change and it came down to 25ppm and 2 days later back up to 50ppm. It was then that i took my water to lfs and they did a test with 3 diffferent API test kits and 2 of 3 gave different results. Did another test with red sea and results were 4ppm. Contacted API on their Facebook page and they gave me long story about how their product is the best there is but never answered my question about the inconsistencies in their test kits.
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If you stop, the nitrogen the bacteria had been accumulating will instead stay in the water.
Over an extended (weeks, probably), the bacteria may slowly die off, releasing the nutrients they contain.
The balance between import and export of N and P in every tank is different based on different creatures, different feeding, and different growth rates, but it is incorrect to think that nitrate only accumulates in an overstocked or overfed tank.
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It can, depending on where the bacteria choose to grow.
I dose into rock filled refugia and have never seen any bacteria, but folks sometimes get unsightly globs in the display tank.
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Reduced nutrients can slow macroalgae growth.
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Yes, although I've heard or more problems with sugar than the other two.
Z06-Hec
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ahhhh, I was stumped for a second... whaaaaaaaat? LOL.
I'm still finding the right dose currently at 3ml a day of just Vodka, it is lowering but its hard to get a proper skim with no ATO. I'm adjusting it daily (skimmer) after a manual top off.
I'm still finding the right dose currently at 3ml a day of just Vodka, it is lowering but its hard to get a proper skim with no ATO. I'm adjusting it daily (skimmer) after a manual top off.
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