Fighting nitrate

[Ruth]

I have been trying to get my nitrate level down for the past month or so. They have been sitting at about 20ppm on my Sailfert test. They would lower somewhat when I did a water change but always climb back up again rapidly. I change about 15% of my water every 2 weeks and had been going to every week to try and get them down. I cut back on feeding and none of this was having any effect. Well yesterday morning I pulled out the big sponges that are in my fuge/sump - I have always taken them out and rinsed them when I do water changes and put them back. Well yesterday I just left them out and also ran carbon with a Magnum 350 for 24 hours. Today my nitrates test at about 2 plus ppm. Amazing - those sponges I think were my problem. Will have to monitor but the sponges are staying out!

[Willow]

run a micron bag and wash it every few days, they work great.

[Beverly]

Ruth,

When you say you rinse the foams, does that mean you give them a quick rinse, or do you squeeze the living heck out of the foams in several changes of water?

Also, do you clean them in tapwater or changewater?

[Ruth]

I was squeezing the bejeezus out of them in new mixed salt water - that is why I did it every time I changed water - I would just make up an extra gallon for rinsing. At any rate I have scrapped the sponges as I think that they might have been my Nitrate trap. I am pretty sure with all the chaeto and mud plus my skimmer my water is flowing through enough "stuff". I left (for now) the sponges in my overflows that fit over my return pipes and will continue to rinse those at every water change. Any recommendations Beverly of what I might be doing better?

[Beverly]

Ruth,

I am assuming the big sponges were pretty dirty when you cleaned them. If so, they were doing the job they were meant to do - which is mechanically trapping detritus. By removing the sponges, that detritus is now staying in your system, unless your other means of detritus removal will do as good a job of trapping and removing the detritus.

IME, weekly cleaning of ALL mechanical filters is a must, especially if there is a nitrate problem. Larger, more frequent water changes are also necessary with high nitrate. I would even go so far as to do two 30-40% water changes in a week for 2-3 weeks to get nitrate as close to 0 ppm as possible.

At any rate, monitor nitrate over the next month or so to see if removing the big sponges actually did anything for nitrate levels.

HTH :smile:

[Ruth]

Actually these sponges were not getting really dirty. My water flows over my overflow, through sponges wrapped around the return pipe, into my fuge, through some rolled up mesh, through the fuge with tons of chaeto in it, then over a divider where it then ran through the sponges to be skimmed and then returned to the display. The really nasty sponges are the ones in the overflows which I clean every week. I don't always use saltwater to clean these and am now wondering if rinsing with tap water - granted from my RO tap is perhaps adding to my nitrate. It is still low today BTW and am still running carbon. Input welcome! :smile:

[Pegasus]

Ruth

I'm sorry but I have to ask. Do you have LR and/or a substrate? The reason that I ask is that since I added LR I haven't had an issue with nitrate. It comes back to the nitrification cycle. The fact that you rinse your sponges in RO water or RO water with salt added will not make a difference.

Larry

[Ruth]

Yup and lots of it - like around 450 lbs between my tank and fuge so I don't think that is the problem.

[Ruth]

Oh and about a 5 inch sand bed as well.

[Pegasus]

Ruth

Have you checked your RO water's nitrate level?

Larry

[Ruth]

Actually no - I didn't even think about it. I am out of water right now but will definately be getting some tomorrow so will check it. Thanks - don't know why that didn't occur to me.

[Psyire]

Wow, 450lbs of LR in Ft. St. John? What is your total water volume? Must be interesting running your tank due to your location. I'm about an hour out of Grande Prairie and I thought I was in the boonies. lol. I have about 250 or so gallons of saltwater under my roof.

[Ruth]

Not actually sure what my net water volume would be. My tank is 230g and my fuge is 77g but of course there is a lot of displacement by the rock.