Getting Frustrated With Nitrates!

[Ellieabbott4]

I've had my tank up and running since December 2012. I've always used the API test strips but have just started using a nutrafin liquid test kit. And I've discovered a problem that the test strips didn't show! My nitrates are through the roof. I've been adding bacteria each time I do a 30% water change. But it doesn't seem to get any lower. I'm worried that it's between 50-110! And I know it shouldn't be that high. My nitrite is between 0.1 and 0.3. My ammonia is 0. I'm struggling to see what I can do to lower the results. In the tank I have 15 guppies and 9 cories. Any help would be greatly appreciated

 

[eaglesaquarium]

First off, the bacteria you are adding will do NOTHING about nitrates.  There are bacteria that will convert nitrate to nitrogen gas, which will escape the water and leave your ecosystem, but they aren't available in a bottle, as they require extremely low flow, and are normally found in anaerobic environments.
 
 
Second, what is the nitrate level of your tap water, you won't be able to effectively drop the nitrates below that level.
 
 
Third, how frequently do you do water changes?  What is the tank stocking?  How much are you feeding the tank?  How well do you clean out the detritus?  All of these will factor into your nitrate levels.

 

[Ellieabbott4]

Oh, my lfs suggested the bacteria so I thought I would give it a try. But no harm done I suppose. Just not right for what I need. My tap water is 10, I thought I would test it to see what it was showing. I thought it might be high to start with but that's not the case. I do water changes every week. The tank stocking is 15 guppies and 9 cories. I used to feed way to much food but now I have cut it down to a small pinch of tetra pro colour and a small pinch of tetra prima once a day. I siphon off any detritus but I don't seem to get much as my malaysian trumpet snails are constantly turning the gravel.

 

[eaglesaquarium]

You did not mention the size of the tank... and that may be the issue, the tank could just be overstocked.
 
 
I've heard of 'nitrate sponges', but have never used one so I can't say how effective it is.  Zeolite (like Seachem purigen) can remove nitrates from the water, but it also can remove ammonia, which can starve your beneficial bacteria.  Adding some (more) live plants can help to control nitrates as well.  Stem plants are the fastest growers and are very good at that.  Even better would be some floating plants like amazon frogbit or duckweed.  These can remove nitrates from the water and then you can just scoop them out if they reduce the light too much for your taste.  (Placing them on your terrestrial plants as a 'mulch' is a great way to take nitrates from what you don't want it and put it somewhere it can help you.)
 
As for the LFS giving the advice, they may have confused nitrite with nitrate, or they could just not understand the nitrogen cycle.

 

[Ellieabbott4]

sorry, the tank is 90l. Ive currently got ergeria densa (massive bunch), two bunches of vallis, java moss and fissidens fontanus moss. but i will try some floating plants if you think they will help as well. i will have a read up about the zeolite.

 

[eaglesaquarium]

The stocking is a little heavy for a 90L, and the nitrates are indicating that.  Specifically the plants I mentioned, not just any floaters... will suck up nitrate.  Duckweed is a dangerous plant to add though, as it will take a LONG time to remove it all once you add it, because it is THAT prolific.
 
http/www.bamaplants.com/index.php?main_page=product_info&cPath=1_17&products_id=297 

(Lemna minor) This is the smallest of flowering plants. it floats on top of the water and can multiply like mad.. in a tank you MUST skim it off sometimes or it will shade the other plants too much. It makes excellent Turtle, Tilapia and other rift lake cichlid food as well as shading ponds to help keep them cooler. This plant also works as one of the BEST nitrate sponges known. and If you skim plants off place it in your house plant pots. It makes an unbelievable fertilizer!!

 

[Ellieabbott4]

i think i will try the duckweed, but when you say it will take a long time to remove....is it that bad?

 

[eaglesaquarium]

Meaning that if you decide later that you don't want it, you may have a hard time getting rid of it all.  Its tiny and a little speck can grow quite a bit in a short amount of time (in other words, its greatest strength and the reason you'd want it - is also the biggest problem).   Its properly called a 'weed'.