Nitrates won't go down! Over 150

[Doctor Faust]

Hello everyone!

I've read a lot on this site previously, but I have just registered.

I have a Red Sea 250, running for about 7 months, fully cycled. I am having a lot of issues with Nitrates and phosphates. I had a huge algae bloom, and then it was gone overnight. What worried me most, is even with literally a few KGs of algae growing in the tank, my nitrates were still over the max of the API test, as in over 160.

I had been changing the water every 10 days most, usually every week, as I have a pretty heavy bioload. Lately, I decided to do a 25% water change every 2-3 days, to see if the nitrates go down. I changed 25% on Sunday, tested, nitrates over max. Changed the water today, wednesday, checked nitrates were over max. There is no algae in the tank currently, my microalgae in the sump (gracilaria) isn't doing too good either. Fish are fine and eating and happy, some corals that I have in there are happy seemingly, but some others I've lost.

My question is, what do I do? Let's say I changed ALL the water and tested and everything showed 0, how soon would my nitrates go over 160? Is it possible that this could be a matter of 2-3 days? If so, assuming I keep changing water every 2 weeks, would that mean my nitrates will be in the few hundreds? And how would that affect the fisH?

Please share some ideas.

 

[Doctor Faust]

Ammonia - 0
Nitrite - 0
Calcium - 400
KH - 7
PH 8.1 (API Reef test kit)
Nitrates - Over 160
Phosphates 2-4 ppm (can't tell if it shows 2 or 4, or more likely in between, as per API test kit)
Lights - 2 Radion Gen 3 15w
Filtration - felt socks, skimmer

I have started to supplement with Seachem's Reef Complete, Reef Plus, Trace.

 

[a49panhead]

R u using rodi water. If not. It could be coming from your water supply. U can test your water supply as well to rule it out

 

[Doctor Faust]

R u using rodi water. If not. It could be coming from your water supply. U can test your water supply as well to rule it out

You know, I don't know if it's DI, as I get it from the store, but it is RO for sure. I've recently set up my own RODI unit and last 3 cahnges are with that water. I've tested and it's undetectable. If I'm changing water 3 times a week at 25%, and right after changing it shows over 160ppm Nitrates, I'm assuming it was in the 3-400s range, which from what I can read, is potentially deadly. All the fish are happy and eating and healthy, and a few easy corals that I have are doing fine too.

 

[dansreef]

What test kit are you using? Just curious.

You say that you have a high bioload. Maybe useful to share the size of your tank and all of the inhabitants and their size. Believe it or not, 7 month old tank is still pretty young.... How did you cycle your tank?

Also, what are you feeding... and how much? I have been guilty to feed my tank as much as the fat pigs ( my fish) would eat. That made problems with export of nutrients a problem. Also, some foods are more of an issue than others.

Also, WELCOME to R2R. I am sure if you can provide some more detailed info, there is a someone here that can help!

 

[Florida Sunshine]

Well, if your source water is coming in at zero it is just basic math. IF your nitrates are 160 and you change 50% of your water you will have nitrates of 80. If your nitrates are 160 and you change 25% of your water the nitrates left will be 120. Then if you change another 25% you are left with 90. So if you are trying to reduce them from a high number you want to do a high percentage of a water change, possibly followed by another etc depending on how high they really are. I would buy and use a different test kit, preferably a different brand and see how the numbers compare between the two.
If you have a high bioload, then you are likely to feed heavily both of which will lead to high nitrates/phosphates unless you do large frequent water changes and/or up your filtration.

 

[EmdeReef]

I would start by making sure the test kit and your interpretation are correct.

Then if you want to quickly drop nitrates, you can start carbon dosing (vinegar, vodka, nopox etc). At that level I would start very slowly to prevent blooms. 1/3 or even less recommended dose and be patient. You should make sure you have some phosphate in your tank too.

Long term you may want to add seachem matrix or marine pure blocks to provide more room for nitrifying bacteria, start a fuge with a good light.

 

[Doctor Faust]

Well, if your source water is coming in at zero it is just basic math. IF your nitrates are 160 and you change 50% of your water you will have nitrates of 80. If your nitrates are 160 and you change 25% of your water the nitrates left will be 120. Then if you change another 25% you are left with 90. So if you are trying to reduce them from a high number you want to do a high percentage of a water change, possibly followed by another etc depending on how high they really are. I would buy and use a different test kit, preferably a different brand and see how the numbers compare between the two.
If you have a high bioload, then you are likely to feed heavily both of which will lead to high nitrates/phosphates unless you do large frequent water changes and/or up your filtration.

Thank you! The math is what's confusing me. Specs first:

I'm using API Master reef test kit, maxes out at 160
I got Red Sea test kit, its lower range, maxes at 50.

It's a 55 gallon, have 9 seahorses, a small walking batfish, fu manchu lion, a few damsels here and there, 2 small tangs 2-3 inch (which I'll be relocating next month), 2 small moonies, a combtooth blenny, 1 lyretail anthias, some crabs, snails, shrimp, stars. Everyone is very happy, including some corals like a torch, hammer, frogspawn, duncan, , so are the feather dusters. Only feather star fish are not doing well long term.

I feed frozen mysis ( I enhance, then drain, then feed), reef mixes, occasionally bloodworms, feeder guppies and some ghost shrimp. Not all at once, of course, as much as they eat, and alternating, except for mysis and a few guppies as a daily staple. Seahorses dont digest that well so their waste prudces a lot of chemicals, I get it.

I did 3 water changes of 25% and tested to be max 160, or could be 1600, test maxes out. If I were to change the water so much within a couple days so that i test 5ppm right afterwards, would it possibly shoot up to over 160 in a day or two?

Filter is running fine, skimmer is doing great, i got 2 chemi pure blue's in there.

Tank is really young I know, and I cycled it anyhow lol. Added this that did almost daily water changes, in the end it took its normal course.

I'm sorry I kind of replied in one post.

And thank you all for the warm welcome!!

 

[Doctor Faust]

I didn't mention some smaller fish in there, like a firefish, pygmy wrasse (1 inch), 3 small leopard wrasses, 1 foxface small, 1 small cowfish, and maybe some more that I'm not remembering.
ALso, on account of the horses, I do feed a lot.

I'm guilty of both overstocking and overfeeding, but in my inexperience I am not understanding just how quickly can nitrates go up? ANd if they go up 200ppm a day, and I don't change it for 2 weeks, which has happened, I would be at 2-3000 range, and from everything I read on forums, anything over 5-10 is kiss your livestock goodbye lol. What am I missing here? And what would be the most cost efficient way to start tackling this?

I am slowly reducing the stock, but feeding can't be any less, as stress kicks in for the slow feeders, so I may need a different solution. I don't mind weekly 25-30 percent changes and maintenance, but it's not cutting it either.

Thank you very much to all of you, in advance and for the given advice!

 

[DesertReefT4r]

Confirm your tests with another source and kit. Have someone else like the LFS do the testing, just to rule you and your kits out. Stop wasting water on so many small water changes. Just do a 100% water change matching SG, temp, alk and ph of your tank. You need to find the source of the high no3. Possibilities are over feeding, not replacing filter socks often enough, something dead decaying in the tank, super dirty sand, waste build up in the sump, or even coming from die off/waste inside rock.

 

[Florida Sunshine]

Well, that is certainly a full tank. The seahorses should definitely be moved away from the rest. Moist importantly away from the lion, but seahorses really need a separate tank because they eat so slowly and so often. Definitely get rid of the tangs and if possible a few more fish. That is a lot to stock in a 55g. I would double check test results and then do 50% water changes probably weekly until dilatation takes it down. With the seahorses, you need to clean their tank daily or close to remove the uneaten food. Otherwise that and their waste will build the nitrates back up.
Are these animals in a temporary tank?

 

[Biokabe]

I didn't mention some smaller fish in there, like a firefish, pygmy wrasse (1 inch), 3 small leopard wrasses, 1 foxface small, 1 small cowfish, and maybe some more that I'm not remembering.
ALso, on account of the horses, I do feed a lot.

I'm guilty of both overstocking and overfeeding, but in my inexperience I am not understanding just how quickly can nitrates go up? ANd if they go up 200ppm a day, and I don't change it for 2 weeks, which has happened, I would be at 2-3000 range, and from everything I read on forums, anything over 5-10 is kiss your livestock goodbye lol. What am I missing here? And what would be the most cost efficient way to start tackling this?

I am slowly reducing the stock, but feeding can't be any less, as stress kicks in for the slow feeders, so I may need a different solution. I don't mind weekly 25-30 percent changes and maintenance, but it's not cutting it either.

Thank you very much to all of you, in advance and for the given advice!

You're not just guilty of overstocking. I'm not trying to be mean here, but you're the patron saint of overstocking.

Simply put, your tank is heading for a major and expensive crash. Your 9 seahorses by themselves are really too much for your tank. In addition to that, you have:

• A walking batfish (75 gallon minimum)
• A Fu Manchu lionfish (30 gallon minimum, but heavy bioload)
• A "few damsels here and there" (two or three would be too many, depending on what type they are)
• 2 small tangs (you should have 0 tangs in a tank that size - tangs need a lot of swimming room, and the least demanding need at least a 75g tank)
• 2 moonies (are these cape moonies/kitefish? If so, okay to have one in a tank your size... two is overkill)
• A combtail blenny (30 gallon minimum, so this one is fine)
• A lyretail anthias (Do best in schools of at least 3-4, and they need a lot of swimming space... 125 gallon minimum)
• A firefish (generally fine)
• A pygmy wrasse (probably fine)
• 3 (3!) leopard wrasses (You really shouldn't have any of these in a tank that's only 7 months old. They're very finicky eaters and require an extremely robust population of pods to survive. 3 in a tank your size would decimate your pod population and begin slowly starving to death)
• A foxface (Depending on the species, 70-125 gallon tank)
• A cowfish (Depending on the species, 90-250g minimum for one of these
• Not to mention, 9 seahorses

You have way too many fish in there, many of which require a tank much bigger than yours. The reason you can't get your nitrates down is because you have a massive nitrate factory in the form of 27+ fish, plus all the food that goes along with them. You can get away with that kind of a bioload in a larger tank, because you have an equally larger amount of live rock + filtration equipment to process those wastes. In a 55 gallon, though, there simply isn't enough room to grow bacterial cultures large enough to denitrify all the wastes. The bacteria that convert ammonia to nitrite, and nitrite to nitrate - those can grow pretty much anywhere in your tank, and they'll size up - to a point - to at least prevent the worst wastes from building up. The bacteria that process nitrate, however, are anaerobic - they only have so many places to grow (mostly in the deep crevices of your live rock). In a 55g, you don't have much space for them to grow, so with a bioload like yours, nitrates are just going to accumulate, and quickly.

Found an old thread on another forum that gave some rough numbers: An adult yellow tang would create approximatley 22 ppm of nitrate per day. You have at least 7 fish in your tank that can produce the equivalent (cowfish, foxface, anthias, two tangs, lionfish, batfish), plus 20+ more that are going to be producing some significant fraction of that. So each day, your tank is producing probably 200-300 ppm of nitrate, if not more. And without enough space to grow sufficient denitrifying bacteria, the only place for that nitrate to go is your protein skimmer (probably not sized large enough to process that much waste) and your overall water.

Simply put, you need to reduce what you have in your tank, or else Mother Nature will reduce it for you. Rehome as many of your large fish as possible - the cowfish, the anthias, the foxface, the tangs, and the batfish all need a bigger tank. The seahorses really need their own dedicated tank where you can set things up to be more friendly to their needs. So, take out those fish and you're down to 12 fish, none of which are too big on their own for your tank. I'd try and fine a new home for the three leopard wrasses - your tank isn't mature enough to provide for them, and three is probably too many for your tank. Now you're down to 9. Probably rehome one or both of the moonies. Now you're at 7-9 (depending on how many damsels you have), which is much more reasonable for a tank that size.

For reference, I have the same size tank as you. I have 5 fish in it: a pink skunk clown, a ruby-headed fairy wrasse, a carpenter's flasher wrasse, a flametail blenny, and a chalk basslet. My nitrates hover between 3-10 ppm, and I feed pretty heavy. For optimal health in your reef, you want nitrates below about 20. Above that and sensitive organisms start having problems - the corals you've lost probably couldn't handle the nitrates. Fish tend to be more resilient, but even they will start to show signs of distress after extended exposure.

 

[Doctor Faust]

Confirm your tests with another source and kit. Have someone else like the LFS do the testing, just to rule you and your kits out. Stop wasting water on so many small water changes. Just do a 100% water change matching SG, temp, alk and ph of your tank. You need to find the source of the high no3. Possibilities are over feeding, not replacing filter socks often enough, something dead decaying in the tank, super dirty sand, waste build up in the sump, or even coming from die off/waste inside rock.

I've started to change the socks more often. You have a good point, most of what you say are things I haven't invested as much as in stocking lol.

By saying "waste buildup in the tank", would barnacles count where the water flows down from the overflow? From all I see online, seems like everyone agrees those are barnacles. I've cleaned most up (there were a lot of them there until i started the current frequent water changes), but there are still some remaining. I figured they might help with the nutrient levels.

 

[Doctor Faust]

Well, that is certainly a full tank. The seahorses should definitely be moved away from the rest. Moist importantly away from the lion, but seahorses really need a separate tank because they eat so slowly and so often. Definitely get rid of the tangs and if possible a few more fish. That is a lot to stock in a 55g. I would double check test results and then do 50% water changes probably weekly until dilatation takes it down. With the seahorses, you need to clean their tank daily or close to remove the uneaten food. Otherwise that and their waste will build the nitrates back up.
Are these animals in a temporary tank?

Seahorses away from lions, why? As in, do you mean the venomous part, or its some other consideration?

Some are in a temporary tank, yes. I will be upgrading in 4 months to a 525L, but if any of these fish grow too large for their swimming space before then, my LFS takes them back

 

[Doctor Faust]

You're not just guilty of overstocking. I'm not trying to be mean here, but you're the patron saint of overstocking.

Simply put, your tank is heading for a major and expensive crash. Your 9 seahorses by themselves are really too much for your tank. In addition to that, you have:

• A walking batfish (75 gallon minimum)
• A Fu Manchu lionfish (30 gallon minimum, but heavy bioload)
• A "few damsels here and there" (two or three would be too many, depending on what type they are)
• 2 small tangs (you should have 0 tangs in a tank that size - tangs need a lot of swimming room, and the least demanding need at least a 75g tank)
• 2 moonies (are these cape moonies/kitefish? If so, okay to have one in a tank your size... two is overkill)
• A combtail blenny (30 gallon minimum, so this one is fine)
• A lyretail anthias (Do best in schools of at least 3-4, and they need a lot of swimming space... 125 gallon minimum)
• A firefish (generally fine)
• A pygmy wrasse (probably fine)
• 3 (3!) leopard wrasses (You really shouldn't have any of these in a tank that's only 7 months old. They're very finicky eaters and require an extremely robust population of pods to survive. 3 in a tank your size would decimate your pod population and begin slowly starving to death)
• A foxface (Depending on the species, 70-125 gallon tank)
• A cowfish (Depending on the species, 90-250g minimum for one of these
• Not to mention, 9 seahorses

You have way too many fish in there, many of which require a tank much bigger than yours. The reason you can't get your nitrates down is because you have a massive nitrate factory in the form of 27+ fish, plus all the food that goes along with them. You can get away with that kind of a bioload in a larger tank, because you have an equally larger amount of live rock + filtration equipment to process those wastes. In a 55 gallon, though, there simply isn't enough room to grow bacterial cultures large enough to denitrify all the wastes. The bacteria that convert ammonia to nitrite, and nitrite to nitrate - those can grow pretty much anywhere in your tank, and they'll size up - to a point - to at least prevent the worst wastes from building up. The bacteria that process nitrate, however, are anaerobic - they only have so many places to grow (mostly in the deep crevices of your live rock). In a 55g, you don't have much space for them to grow, so with a bioload like yours, nitrates are just going to accumulate, and quickly.

Found an old thread on another forum that gave some rough numbers: An adult yellow tang would create approximatley 22 ppm of nitrate per day. You have at least 7 fish in your tank that can produce the equivalent (cowfish, foxface, anthias, two tangs, lionfish, batfish), plus 20+ more that are going to be producing some significant fraction of that. So each day, your tank is producing probably 200-300 ppm of nitrate, if not more. And without enough space to grow sufficient denitrifying bacteria, the only place for that nitrate to go is your protein skimmer (probably not sized large enough to process that much waste) and your overall water.

Simply put, you need to reduce what you have in your tank, or else Mother Nature will reduce it for you. Rehome as many of your large fish as possible - the cowfish, the anthias, the foxface, the tangs, and the batfish all need a bigger tank. The seahorses really need their own dedicated tank where you can set things up to be more friendly to their needs. So, take out those fish and you're down to 12 fish, none of which are too big on their own for your tank. I'd try and fine a new home for the three leopard wrasses - your tank isn't mature enough to provide for them, and three is probably too many for your tank. Now you're down to 9. Probably rehome one or both of the moonies. Now you're at 7-9 (depending on how many damsels you have), which is much more reasonable for a tank that size.

For reference, I have the same size tank as you. I have 5 fish in it: a pink skunk clown, a ruby-headed fairy wrasse, a carpenter's flasher wrasse, a flametail blenny, and a chalk basslet. My nitrates hover between 3-10 ppm, and I feed pretty heavy. For optimal health in your reef, you want nitrates below about 20. Above that and sensitive organisms start having problems - the corals you've lost probably couldn't handle the nitrates. Fish tend to be more resilient, but even they will start to show signs of distress after extended exposure.

Thank you so much for a thorough reply!


I didn't know all of what you said about nitrate processing bacteria. Thanks a lot. As well about the numbers. Now those talk to me. Those numbers would explain why the numbers didn't seem to move, especially when my test maxes out at 160.

Thankfully my skimmer is good, rated for 130/60heavy, and rock I have a lot for the tank size, but yeah, I bet not nearly enough for the load.

As to the fish, here's what I'd be willing to do lol. Please tell me if this would be sustainable for 4 months, with weekly water changes:

-Damsels all will be gone. They're food, and if not eaten in a few days, I"ll take em to my office tank and they'll be happily eaten there.
-Moonies as in Mono Argentus. They will go either in the mantis tank, or back to LFS. I don't like their personalities, or perhaps lack thereof.
+/-tangs are about 2 inches currently, you think they'd be thaaat bad for the next 4 months? I mean I can rehome the chocolate one once I see the chocolate on him. If they wont make it that long, then I'll part with them too, not too attached. Otherwise plan is to meet their adulthood in the big tank in 4 months.
+ Cowfish will be fine as far as space is concerned for 4 months until i set up the 525. He's still like 2.5". Right? I mean those minimum requirement sizes are for grown adults, long term housing, right?
+/-Foxface I could give up too. Not too attached, but he's still small, want to enjoy for a couple more months. He's 2-2.5"
-Firefish was eaten solved that problem I guess.
+Batfish is small too. It's not the longnose subspecies that gets to 9.5 inches. Doesn't take up much real estate, and I keep him fed. I believe I can manage him for 4 months.
+Seahorses are all staying lol It either has to work or it has to work.
+Lionfish is staying for sure.
+Anthias I like. He looks fed and happy, it eats mysis and brine and pods that I fill up every week. Used to have 2 spotted and 1 ruby red dragonets up until a few days ago. They joined the firefish. If this guy survives, I wanna keep him.
+Leopards are eating very well all the mysis, brine and worms and all the bits of live food that they can get. All 3 are different kind, but I donno how it works out for them as far as genders and such, but they are peaceful. Honestly, if it stays as is between them, I'll keep all of them for the big tank.

The ones I have as +, do you think I can manage those for 4 months? Also, do you think they will be fine for 2-3 years in the 525L? I mean I'm willing to do the water changes, and even got an R/O unit, but I'm hoping to cut down my maintenance SIGNIFICANTLY when I switch to the larger tank soon.

Also, I don't mean to be asking you personally all these questions, but you brought up some detailed points that have always piqued my curiosity, but now it's more about some practical solutions. So anyone's input is greatly appreciated!

 

[Hemmdog]

Your lionfish is what’s eating all your fish. Why would you want to keep that? I feel bad for the damsels ;Panda

 

[Doctor Faust]

Your lionfish is what’s eating all your fish. Why would you want to keep that? I feel bad for the damsels ;Panda

What about the poor lionfish though? Everyone's gotta eat. Damsels are eating very finely too. I'm in the hobby to take something out of recreating nature in tiny episodes, rather than running a rescue mission. It's not the lion anyways. He seems to prefer the marine plankton fed saltwater guppies. I brought a helper from my office tank lol and he ate all the wrong fish so far :/

 

[mattzang]

LOL dang i thought my tank was overstocked with 9 fish in a 50 gallon, this guy knows how to party

 

[Hemmdog]

LOL dang i thought my tank was overstocked with 9 fish in a 50 gallon, this guy knows how to party

Hahahaha

 

[Hemmdog]

What about the poor lionfish though? Everyone's gotta eat. Damsels are eating very finely too. I'm in the hobby to take something out of recreating nature in tiny episodes, rather than running a rescue mission. It's not the lion anyways. He seems to prefer the marine plankton fed saltwater guppies. I brought a helper from my office tank lol and he ate all the wrong fish so far :/

Set up a species tank for the lion fish, and a species tank for the sea horses. Then put your reef safe and friendly fish in this 500L your getting if you really don’t want to get rid of some of them. Truely though, try to find them homes, sea horses aren’t super cheap and a lot of people would LOVE to have them in a species tank.

And the hunger games style survival games is not helping your nitrates lol.