Nitrates

[Bryan619]

I have had my 55 tank cycled and running for a about a month now. I do a 15% pwc every week but it doesn't seem to bring my nitrate levels down. My tap has 0 nitrates. I have a penguin 350 hob filter. It says to change the media every 2 weeks but I wanted to wait a little longer on the initial setup for the good bacteria to colonize. Could this be why the nitrates don't go down? Right now they are between 40-80 ppm. Is there something I could do (besides live plants)? I'm going to replace 1 filter cartridge tomorrow the other on Sunday. Sorry. 1 other thing. In my filter their is a slot for extra media. Can I use a pad from a diff company that I have? Or part of a sponge filter?

[Chrispixx]

15% of 55gal is only 8.25 gal that is not alot or enough water for that big of a tank. i change 30% or 16 gal in my 55 once, sometimes twice a week, but my fish are big. the bigger your fish get the more water per week you will have to change. hope you are not using buckets, you might want to look into getting a Python or making your own DIY python.

Speaking of big fish your bala sharks will out grow your tank as will the albino channel cat. when the catfish gets bigger it will eat your tetras. Google is your friend when buying fish so you know what they're compatible with and how big they will get.

albino channel cat.



As far as nitrates go i don't bother testing anymore, it gets like that the more advanced you get,just change the proper amount of water per week and everything will be fine. its been years since i tested for nitrates so i couldn't say when the last time was. my 55 is pristine and the fish are close to ten years old. ( i wish i had saved the receipt so i knew exactly how old they are)

Regarding the penguin hob filter they say to change the media because they want you to buy their stuff. and if you change the media you will lose your bacteria colony. i have three of the same filters, do you know the last time i changed the media? i cant remember that far back. all you need to do is put some tank water in a clean bucket, preferably a bucket that has never had soap in it. swish the media cartridge around in the bucket and scrape the pad with your fingers to dislodge the debris then put it back in the filter. one more tip, before you pull the cartridge from the filter get a net big enough to fit that side where the water is falling out, use a clothespin to hold the net there and it will catch all the crud that would other wise go in your tank.

[Bryan619]

Thanks for the info. The balas and channel cat r baby's. The channel will go outside in the pond. The balas will either go into a bigger tank (if I ever get it) or my lfs said he would take them back from me.

[emc7]

You can reduce the creation of nitrate by feeding less and removing as much debris mechanically as you can. Rinse cartridges, gravel wash substrate.

Nitrate is the end product of the FW "cycle". All food and dead plants, fish and algae in a FW tank ends up as nitrate. And, unless you have plants or algae consuming nitrate, the concentration will just keep going up. Changing out media may slow the conversion of ammonia and nitrite to nitrate, but as nitrate is the least toxic, that is not a good thing. Rinse media, but replace only when it starts to fall apart or you need fresh carbon to remove meds, smells, or oily film.

Changing water is usual method to remove nitrates. And its a concentration math. So to reduce nitrate from 80 ppm to 40 ppm, you have to change half of the water. Small changes are multiplicative, rather than additive. So 20% + 30% doesn't equal 50%. Its (1-(.8*.7))*100% = 44%.

There are a bunch of new products marketed to aquarists to get "rid of nitrate". They have names like "sludge away" and claims like "never change water again". Do NOT use these in a tank with fish alive in it. They run the cycle backwards from nitrate to nitrite to ammonia to nitrogen gas. The higher your nitrate level, the more dangerous it is to convert it back to ammonia. They also attack slow-decaying crud in the tank like dead algae. The nitrogen gas is safe and soon the water will be nitrate free, but by then all the fish are dead. In theory, you could use such a product constantly and have only low levels of ammonia in the tank, but I have heard too many horror stories to consider risking it. IMO, they are only useful if you are cleaning an old filthy, fish-free tank.

There are few other methods that have some utility. One is to use a substrate that will chemically remove some nitrate. These have some use in high pH and hardness cichlid tanks.

Another is an ion exchange resin. An ion exchange resin in a pouch in the filter will take up nitrate and release another ion, usually chloride, in its place. There are more that a few drawbacks here, too. You add salt to the water, not good for many plant and inverts. When the resin is exhausted it stops taking up nitrate. But more of an issue is that these things aren't that selective. They often take up nitrite also. If you consistently remove nitrite as it is created, the nitrite to nitrate bacteria will starve. When the resin is used up (you can recharge with salt), you suddenly have a huge nitrite spike, which again can kill fish.

If you go with ion exchange or any other chemical nitrate removal method, you need to be testing all the time until you work out a process and schedule that keeps your fish alive and nitrates controlled.

Testing nitrate is a decent way to figure out what your water change schedule should be. Keep nitrate low, and likely all the other bad stuff is in check also. You will have to ramp up water changes as fish grow and get fed more.

[Chrispixx]

Originally Posted by Bryan619 In my filter their is a slot for extra media.

having the same filters, mine came with a plastic basket that slides in the back slot. if you have the same type you can put bio media in there, carbon or both.

Originally Posted by Bryan619 Thanks for the info. The balas and channel cat r baby's. The channel will go outside in the pond. The balas will either go into a bigger tank (if I ever get it) or my lfs said he would take them back from me.

cool

[Bryan619]

Thanks everybody for helping out. Yeah I don't want to add any chemicals. I just have to change more water more often. Python it is cuz I dread the bucket system.