nitrate spike

[MiMiC]

as the title says, i have 20-25ppm nitrates ive had my tank up for 4 months I read every tank goes through a nitrate spike in which with only time it will regulate and come down which is why they say tanks are not matured till 6+ months - is this normal? i feed regulary and do water changes once a week (once every 7 days) i take out atleast 5g's at most ive done a 10g water change and nitrates went down maybe to 15ppm now they are back up, stocking is in sig i feed every other day, only what they eat right there and then, feed phytoplankton every 2 days, about a tsp worth, i am assuming my nitrate spike is due to the regular feedings (2-3) times a week for my Sun Coral but I could be wrong, ive taken out my bags with carbon and other filtration and cleaned them and they still will not go down, should i be worried I read not to stop feedings because its not like they go down overnight and that my system will regulate with time (bacteria will grow) to help lower my nitrate levels, i want to get some macro algae to see how much it will help since its purpose is to take excess nutrient out of the water, I do skim not to heavy every day i get a cups worth of thick bubbles sometimes its white sometimes its brown, i am sure i am not overstock, I COULD be overfeeding somehow probably my sun coral, if this is the case I think I will have to find it a new home since taking it out every time i feed is a little bit too much trouble for me.

 

Let me know what you think.

[Mr. Fosi]

Carbon doesn't bind anything for NO3. Bacteria doesn't sequester NO3.

 

You high NO3 is probably being caused by your feeding schedule.

 

Do you use macroalgae as nutrient export?

 

You should read this: http://www.nano-reef.com/articles/?article=17

[MiMiC]

What I meant is I cleaned the bags, to make sure detritus didnt build up on it so i was scratching them out of the possibilities on why my nitrates are high (thought maybe detritus had settled on them but they were pretty clean even before cleaning them.

 

I will try to feed less, do you think twice a week is enough, could I cut it back to once a week? I feed every 2 days.

[Mr. Fosi]

Twice a week is good, just don't load in too much food during each feeding.

[MiMiC]

I dont think I do but obviously I am so I'll cut down on food, also the juice from mysis that I use to get my Sun Coral to open, that adds alot of nitrates? I use about a syringe full and I get all the polyps a good wiff of it. And usually let it sit like that for about 20 mins then it fully opens in which time I feed it a cube of mysis or brine, I might start feeding it peices of krill since its less messy.

[Mr. Fosi]

You should thaw and strain your mysis before adding them to the tank. That juice does contain a lot of nutrients including nitrogen and phosphorus compounds.

[HankB]

I'm going to piggyback on this discusion.

 

Our tank has been up a week (9 days actually) and was started with water, sand and rock from our dealer's tanks. The rock was out of the water about an hour before we got it in the tank and back under water. (We splashed some tank water on it as soon as we got it home.)

 

A couple of mushrooms and a Cerith and an Astrea snail survived the transport (along with a bunch of smaller critters.) At day 4 we started to see diatoms and on day 5 noticed 'pods. Now there is some green algae too.

 

Since day 1 we have been testing water chemistry - Nitrates daily and ammonia and nitrites at least every third day. We have never detected ammonia or nitrites - which does not surprise me. Our nitrates started at 10 and is now at 20.

 

Our only mechanical filtration is a handful of floss sitting on top of a sponge. I change the floss every two or three days to get the stuff it collects out of the tank.

 

We started our water changes at about 15% on day 5.

 

We're not feeding anything yet and I suppose the nitrates are coming from some limited die off resulting from the move (from dealer tanks to ours.)

 

I've searched for comments on nitrates and most are "mine are at zero" or "they should be at zero." I did see one keeper that claimed that nitrates up to about 20 were not generally a problem. The snails are happy now that algae is growing and so is the mushroom as near as I can tell.

 

So... Should I be concerned about the levels we are seeing? My expectation is that the algae will use it up and I should be adding more CUC to take care of that. Eventually denitfifying bacteria should start to deal with this but my understanding is that takes about 6 months to get going.

 

thanks,

hank

[Mr. Fosi]

So... Should I be concerned about the levels we are seeing?

 

No. You just haven't reached the end of your die-off. You aren't seeing NH3 and NO2 because your bacterial populations are large/active enough to keep them undetectable. You see the NO3 because it is building up faster than it can be used.

 

My expectation is that the algae will use it up and I should be adding more CUC to take care of that. Eventually denitfifying bacteria should start to deal with this...

 

Yes... Kinda. You will probably not have a NO3-denitrification balance because the denitrifiers are limited by the amount of labile dissolved organic carbon available to them. The algae will eventually start to take up the NO3 in force, but (IMO) it is a good idea to do a large waterchange before that happens.

 

... but my understanding is that takes about 6 months to get going.

 

Maybe. Depends on how much dissolved organic carbon you have floating around your tank.

 

Have you read my article on the nitrogen cycle? There's a link in post #2

[HankB]

Have you read my article on the nitrogen cycle? There's a link in post #2

 

Yes, but I had probably better review before the test.

 

Also I was not sure how much the cycle would differ starting with stuff form another tank. This is really the equivalent of moving a tank (that includes disturbing the sand.)

 

Thanks for the article! It was not immediately obvious that Mr. Fosi == IMH.

 

There's some cool stuff going on in the tank but I think I'll put that in another post.

 

-hank

[Mr. Fosi]

Also I was not sure how much the cycle would differ starting with stuff form another tank. This is really the equivalent of moving a tank (that includes disturbing the sand.)

 

In theory, nothing. In reality, people's experience runs the gamut.

 

Some people move a tank (or build a tank with established rock + sand) and have no cycle whatsoever. Others end up with a situation like yours. The most plausible explanation is that some things died in the move and are still dying/decomposing.

 

It could just me microbial populations or it could be worms in your rock or many other things.