where do nitrates come from

I have had a saltwater tank for about 8 months now and have fought nitrates from the beginning....not drastic but usually around 40ppm which isn't acceptable for so many things...well tonight i was doing a little studying on ways to lower them as i have done many times in the past and ran across a interesting theroy.......getting them in my RO water that i buy from the local water store i just thought because i purchase it it is ok and never tested it before i put it in the tank ....well i did and the nitrates were around 80 PPM to my surprise..well i will be shopping around for another place to buy my water and testing it before i use it........I just wanted to share this info with all of you.....

 

Thanks, Aquagirl! Karma to you!
When I was using Wal-Mart bottled water, I had the same thought as you and tested it.But, it only had readings of 5ppm.
The water from my new Air, Water & Ice RO/DI unit has zero nitrates.

 

Ive thought about using distilled water, any comments?

 

Distilled is to pure but there are some replenishing elements you can add to that But My main concern with using distilled water would be was it ran through a copper coil or a lead or zinc tubing maybe even black tin tubing was used. like was used on old soda fountain for Carbonated water.. Not a good idea unless you know for certain how it was distilled.. I would never chance the use of distilled water Maybe you might want to look at getting your own filtration system ? I have several family members who distill LOL in the hills Va. They use copper tubing only . But their water would be far far to pure for a fish tank of any kind Moonshine honey dew mountian water

 

here is a little follow up from my earlier questions about the water from the local water store....I took my little test strips to two more water stores in the area and got the same readings between 60-80 nitrates in the fresh water .......so how do you start off with this and get the nitrates down to 0?

 

Might want to get a regent type test kit first the strips may be old or contaminated in some way ? But if they are a problem in the tank there are several methods to remove them If you are over feeding with meats that will cause them as will over feeding in general ..

 

Why don't you just get an RO/DI unit off of ebay for less than $100 shipped like I did and be done with the naitrate problems. Mine hooks to the faucet and I fill my jugs when needed. I've been running this unit since starting this tank and have yetr to get any algae problems.

 

You do have a beautiful tank, Apollo'sowner. It makes for a strong argument for using RO/DI water (and not overfeeding!).

 

Thanks. I really thought that an RO unit was a neccessary. But lately I have heard of people using tap water. I know I am probably stepping on toes, but I can't understand how someone would invest hundreds and even thousands of dollars on corals, one of the most delicate animals we can keep in our homes, and yet supply their basic need-water-not knowing what is in it, whether tap or store-bought bottled.
What's to say that the label on the bottled water is acurate? And tap water? At work teh facets get a build-up of brown goo over time. I would never drink it unless there was no other available, much less put it in my reef tank. With the low prices or RO/DI units and the ease at which they can be operated, there really is no excuse to not have one. 3 acro frags cost more than a small RO/DI unit. I split a ricordia rock with a girl in the LRS the other day and she bought a large brain and her bill was over $140 and yet she uses tap water and fights algae. $140 could have gotten her a good unit with some change back. Doesn't make sense.
It should be one of the first pieces of equipment we buy.

 

but why are nitrates harmful what do they do to be so harmful??