Reduce nitrate in saltwater tank
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Randy Holmes-Farley
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There are many good ways to reduce nitrate. The least expensive are probably growing macroalgae and dosing organic carbon (like vodka or vinegar).
I use vinegar dosing, skimming, growing macroalgae, big rock filled refugia, activated carbon, and water changes.
Others include various sorts of denitrators.
I discuss and compare methods here:
Nitrate in the Reef Aquarium - REEFEDITION
https://www.reef2reef.com/blog/nitrate-in-the-reef-aquarium/
I use vinegar dosing, skimming, growing macroalgae, big rock filled refugia, activated carbon, and water changes.
Others include various sorts of denitrators.
I discuss and compare methods here:
Nitrate in the Reef Aquarium - REEFEDITION
https://www.reef2reef.com/blog/nitrate-in-the-reef-aquarium/
Bbaz123456
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A refugium is a great way to go. It is my main method of exportation and I certainly do not have a fuge half the size of my dt. Anything would help even a 10 gallon. Mine is about 15-20% of the main tank and I feed very heavy and have lots of fish. It is very low maintenance and has many benifits besides lowering nitrates.
Feltman
Active Member
You mentioned it's a new tank did you properly cycle the tank before adding fish? Biggest thing with nitrates are to much fish (waste) or to much food(waste), it could be possible the food is getting caught in ur rockwork(either rocks packed to tight or not enough flow).
In 2 tanks (one mine, one for a doctor's office) I feed tons (of clean food - DIY and LRS) and never have any detectable nitrate (well maybe 0.1-0.2) using Salifert looking sideways through the vial and also low Phosphate (hanna checker, 0.01-0.03 usually), running just an algae scrubber for filtration. And not that I recommend this but I haven't done water changes on either of these tanks in over 2 years. That was mainly due to circumstances and I'm now switching to Aquacraft Bio-Sea Marine and firing up the water changes again. Mainly because 1) it's really not a good practice 2) I want to be able to add some different coral and 3) Bob Fenner convinced me (fest speaker) 4) tired of Reef Crystals sludge that I "thought was normal". So now I can say you can get away without doing water changes and have no N or P, and why not to do it.
evmibo
Active Member
CerMedia MarinePure 8x8x4 block. Anaerobic bacteria grow within and nitrate drops. Set it and forget it, although I rotate mine every 3-4 months.. Helped drop my nitrates from ~25ppm to <1ppm.
I had used a refugium and growing chaeto like crazy but they can never get below 15ppm. My tank is a heavily stocked mixed coral tank with lps and softies. My tank is a 60g cube so there's not much space under the cabinet so I switched to a bio-pellet reactor using carbon pellets. I then seeded the filter for 3-4 days of the proper bacteria and now it's been 2 months, my nitrates are at 5ppm. I don't want to go any lower than that. Corals do need a little nitrates for proper health.
You also need to do your weekly mini water changes but I don't really change my water that often. Once a month is when I do my changes (but I don't recommend this).
Hope the info helps and good luck.
You also need to do your weekly mini water changes but I don't really change my water that often. Once a month is when I do my changes (but I don't recommend this).
Hope the info helps and good luck.
Harold Green
Well-Known Member
Several members have asked how new your tank is. I would imagine they're thinking your tank cycling may not have been fully completed yet. If the tank is too new it may not have enough bacteria to consume the nitrate or the bio-load hasn't been high long enough for the bacteria to catch up.
All Delight
2500 Club Member
Big water change will solve the problem quickly. But you need to find out what is causing the problem otherwise it'll just come back. Big water change isn't as traumatic as most reefers make it out to be. Mix your water temp to tank temp and you can do a 50% water change without issues. That will slice your nitrates in half.
if you failed to do the 90% wc after the cycle completed, you will have remnants of it forever.
generally tanks gain 40ppm no3 after a cycle. 10% wcs would not make a dent in it, much less the addition of new fish.
are the nitrates just hanging in the same spot with your husbandry practices? or are they slowly dropping?
this is what i would do as well. more like 75% though.
care should be given that the temp and alk remain constant.
generally tanks gain 40ppm no3 after a cycle. 10% wcs would not make a dent in it, much less the addition of new fish.
are the nitrates just hanging in the same spot with your husbandry practices? or are they slowly dropping?
this is what i would do as well. more like 75% though.
care should be given that the temp and alk remain constant.
Harold Green
Well-Known Member
Russ excuse my asking but where did you come by this 90% water change after a cycle. I've never heard of changing water after cycling a tank unless you've added more of an ammonia source than the bacteria is capable of handling. My tanks generally show little if any nitrates after six to eight weeks. It takes a while to get nitrate reducing bacteria established and enough low oxygen habitat for them. Doesn't work well with shallow sand beds and tanks with little appropriate live rock. My tanks mostly had plenum systems but my main display has a sump with refusium. I remove a small amount of macro algae every month or so. Very slow growth due to lack of phosphates and nitrates. I also have a dozen or so large clams that I believe remove some amount of nitrate from the water. I have to agree with All, in that if you have nitrate in your water you need to find out where it's coming from rather than just trying to keep it in check with water changes.
OP
OP
Purpule Tang
Active Member
Mr.prdubios I have a reef octopus nwb 150 for 90 gallon tank.is ok?
if you cycle the liquid route (pure ammonia or windex or whatever) a common practice is to dose until 1-3 ppm and then keep adding to retain it. i do not see this happening with a dead shrimp.
upon retaining that concentration or a fraction thereof, it is very common to have 40 ppm+ nitrate at the end of 6-8 weeks.
the bacteria exponentially increase, and more is needed to retain it at the designated level.
i could see the confusion with more advanced aquarists not following this method, however it is popular.
hope that clarifies things
