Silly nitrate question

[2_zoa]

So, I can't get my trates below 25ppm-salifert. I did some testing and my top off reservoir tested 2-5. Which is where my question comes in.

Does this mean that I'm adding 2-5ppm for every liter of top off water that goes into my tank? If so, that means my half gallon or 2 liters of top off is adding 4-10ppm nitrates, right?

I never could grasp dilution or concentrations. Simple I know, just not for me. I always confuse myself.

 

[bertoni]

I would double-check the test kit. Are you using tap water? That might have some nitrate in it.

What is the total volume of water in the tank? Your topoff probably has very little effect on the nitrate level in the tank.

 

[2_zoa]

It's a 65 gallon tank. After displacement I probably have 45-50 gallons of water. I don't have a sump.

I'm using RO/DI water. Although the filters are VERY old. I've not changed them since I bought it. Probably 4 years, 5 years. I haven't changed them as I only get 1 or 2 ppm TDS reading for a min or two right at start up. I don't make a whole lot of water. Really just top off water. Maybe 300 to 500 gallons a year.

Given that info, I have wondered about a build up of detritus and what not. So, I siphon the sand bed and I have a racking cane that I use for cleaning the rocks. That water is let to sit for a half hour to decant and then placed back into the tank. That's how I've been removing the solids from the system. My phosphates always read zero on my Hanna checker. It's the 713 model.

How would I check the test kit other then to buy another one to check it against?

 

[Randy Holmes-Farley]

So, I can't get my trates below 25ppm-salifert. I did some testing and my top off reservoir tested 2-5. Which is where my question comes in.

Does this mean that I'm adding 2-5ppm for every liter of top off water that goes into my tank? If so, that means my half gallon or 2 liters of top off is adding 4-10ppm nitrates, right?

I never could grasp dilution or concentrations. Simple I know, just not for me. I always confuse myself.

No.

If the top off is 4 ppm nitrate (is this RO/DI?) and you add 1% to the tank (1 gallon of top off for 100 gallons water volume), it boosts nitrate by 0.04 ppm with each addition. Same for a half gallon into a 50 gallon tank, but I don't know your exact tank size.

 

[Kungpaoshizzi]

What else is in the tank producing nitrates would be my first question.. (decaying stuff, fat fish, unclean reactors, something died, plant matter)

 

[2_zoa]

So, it's the values that confuse me. The kit reads in mg/l or ppm. One in the same right? If Randy's example is 1 gallon of 4ppm water diluted in 100 gallons giving a .04ppm concentration. That's easy. Thank you by the way. How does the mg/l cross over. There's more then 1 liter to a gallon? That's where I get lost. I look for "linear" if you will, comparisons. It seems to me that there is no value or set volume.

 

[Randy Holmes-Farley]

I'm not sure I understand the final question. Just think of it as ppm and don't even worry what the units actually mean.

 

[2_zoa]

Haha. Ok. So, my top off water is not my problem then. I will look elsewhere.

Thank you all and stay dry.

 

[Buzz1329]

Given that info, I have wondered about a build up of detritus and what not. So, I siphon the sand bed and I have a racking cane that I use for cleaning the rocks. That water is let to sit for a half hour to decant and then placed back into the tank. That's how I've been removing the solids from the system. My phosphates always read zero on my Hanna checker. It's the 713 model."

What's a racking cane? Do I understand correctly that instead of doing regular water changes, you are removing detritus and tank water from the DT, letting the detritus settle, and then pouring the old water back into the tank?

If so, I would think that that's your NO3 problem right there.

Good luck

Mike



How would I check the test kit other then to buy another one to check it against?

 

[2_zoa]

your response is in the quote right? It won't re-quote you for this post.

The decanting isn't my idea. I read about it a good bit ago on the oregan reef web site. He had a different method. Never the less, how is it my No3 issue?? The solids have been removed and the clear water back. Yes, the water has No3 in it but.....

Simple water changes (large ones) are a poor way of controlling a No3 issue. I'm trying to find the root of the problem. Not just dilute it. If my biological filter was strong and working proper (I don't think it is now, after this thread) the tank would process the daily nitrates and not be an issue for me/the tank. I could buy or build a sulphur denitrator but, again. I feel it's a band-aid. I could setup/alter my sand bed to do the same.

 

[bertoni]

I agree that water changes generally are a poor way to handle a nitrate problem because the level can jump back up very quickly if there's an underlying issue.