NYC Tap Water In Reef Tank?

roboshark · Dec 7, 2016

I am new to the reef keeping hobby and will be starting up my first 10 gallon nano reef. I have searched up answers to this question, but have found that some people claim to have had success using tap water while others have had tanks crash as well as algae blooms. Tap water also has fluctuation in terms of contents, and different places will give different results. My question is will it be okay to use my New York City tap water in the 10 gallon when I set it up? I have a bottle of dechlorinator and have heard that leaving the lid off will allow the water to fully dechlorinate. Also, many say that the initial TDS will rise with evaporation and that adding more tap will cause a skyrocket in harmful chemicals in the tank. If I have a sealed lid, and only take it off to do water changes, will the water stay at a constant TDS (aside from dosing?) I would like to keep fish, coral, and invertebrates in this tank. However, a more reasonable approach would be to just have a FOWLR tank. Also would it be possible to keep coral in a tank that may have a small amount of copper from the tap?
If using tap water is not an option, are there any filtration methods you have used to purify the water without an RO/DI filter? At the moment I can't afford to buy a system. Something I also read about was using Chaeto or something similar to remove certain toxic chemicals. Would this work at all?

Thank you!

GatorGuys · Dec 7, 2016

I started out using tap water (Rocky Mountain fresh water).... While it worked (we have low TDS - somewhere around 20 to 30 ppm), I did have some troubles with high Silicates. Come to find out, our water has fly-ash (a coal by-product) added to keep the very pure water from corroding the pipes. During the summer, the city I live in pulls water from a second source - which turned out to have phosphate.

Again, my TDS was still relatively low 20 to 30 ppm - but the combination of silica and phosphate being constantly added to the tank eventually led to a massive algae-bloom.

One issue with using tap water - even with a low TDS is that over time, your tank will accumulate the solids. For example, I was dumping 30 ppm silica into the tank every water change. The water would evaporate out of the tank - which meant I had to top it off with more water. The new water added another 30 ppm TDS... and the cycle continued. Over time, the 30 ppm became hundreds of ppm as there was no effective way to export (water changes can only remove so much - and I was ADDING up to 30 ppm back in anyway).

Long story short, save up for a RODI system. Until I could afford it, I purchased RODI water from my local grocery store. In the long run, a RODI system will actually SAVE you lots of money, time, headaches, and frustration.

beaslbob · Dec 7, 2016

roboshark said:
I am new to the reef keeping hobby and will be starting up my first 10 gallon nano reef. I have searched up answers to this question, but have found that some people claim to have had success using tap water while others have had tanks crash as well as algae blooms. Tap water also has fluctuation in terms of contents, and different places will give different results. My question is will it be okay to use my New York City tap water in the 10 gallon when I set it up? I have a bottle of dechlorinator and have heard that leaving the lid off will allow the water to fully dechlorinate. Also, many say that the initial TDS will rise with evaporation and that adding more tap will cause a skyrocket in harmful chemicals in the tank. If I have a sealed lid, and only take it off to do water changes, will the water stay at a constant TDS (aside from dosing?) I would like to keep fish, coral, and invertebrates in this tank. However, a more reasonable approach would be to just have a FOWLR tank. Also would it be possible to keep coral in a tank that may have a small amount of copper from the tap?
If using tap water is not an option, are there any filtration methods you have used to purify the water without an RO/DI filter? At the moment I can't afford to buy a system. Something I also read about was using Chaeto or something similar to remove certain toxic chemicals. Would this work at all?

Thank you!

IMHO yes it does work and very well. By starting the tank with a refugium of chaeto or other macro algae you balance out and stabilize the system. If you keep the macro algae thriving you can just top off water that evaporates and the tank will basically take care of itself. Even copper is filtered out by the algae for exporting when you harvest it.

That said Paul_b has been running a reef tank in New York city for over 40 years. He did switch to ro/di water a decade or so ago after some problems with corals and he found out there was some additive affecting the corals.

you might check out his threads.

my .02

MaiReef · Dec 7, 2016

Get an RO/DI system. Not that expensive and if you have a tds meter, you always know.

drawman · Dec 7, 2016

If you're looking at getting corals and invertebrates it would make much more sense to save your money towards an RODI unit. Maybe you can find a used one and replace the filters at a discount. I would keep an eye on the dry goods selling portion of this forum. A lot of things are expensive in this hobby but IMO an RODI unit is one of your best investments for long term success.

PatW · Dec 7, 2016

Like everyone else, I would recommend getting an RODI system. My tap water is about 120 TDS. It comes out of the RO membrane at 2 TDS and out of the DI ar 0 TDS. The RODI water pretty much guarantees a high and consistent water quality. You never know what is going to be in tap water. It could be copper which would wipe out your invertebrates. It could be traces of pesticides, herbicides, drugs, phosphates or nitrates.

I think spectrapure sells refurbished units for about $100. Wiping out your livestock will cost you far more.

recess62 · Dec 7, 2016

Using RODI will save you from headaches down the road

__Jreef__ · Dec 7, 2016

Get a RODI unit, I live in the NYC area and you will be surprised how much stuff I find in my filters.

amazonjoe · Dec 7, 2016

I agree with everyone, save up a purchase a RO/DI unit. You can buy one for under $100. Look at Amazon. Aquatic Life RO Buddy is one. Just search for it. I would do more reading and research for now and save up. I would not start with out using RO DI water. You will enjoy the hobby more.

Randy Holmes-Farley · Dec 7, 2016

While I have not looked recently, for an older article of mine, I showed that New York City reported in 2002 that 10% of homes had more than 310 ppb of copper in their tap water.

http://www.advancedaquarist.com/2004/1/chemistry

IMO, that is too much, and since the copper comes from your own pipes, even your next door neighbor using it OK does not mean that you can.

Paul B · Dec 7, 2016

I used NYC water for about 20 years or so and NYC had some of the cleanest water in the country because it comes from upstate reservoirs which are about 22 miles from the city. The tunnels were built out of cobblestones well over 100 years ago and run 900 feet below the city. The problem is that a few years ago we opened up one (or two) of the new water tunnels as the old tunnels probably leak more water than they carry. I was in the new tunnels and all that construction debris, metal, chemicals, dead pigeons, frankfurters and other stuff that comes off new concrete will infuse into that water for the next 100 years so it is no where near as good as it was. You could use it of course, but you may have some problems.
By the way, the NYC water tunnels were the longest tunnels in the world until they built the "chunnel" between London and Paris.
I think the copper in New York City water comes from home plumbing because PVC plumbing was always illegal here, I am not sure if it is changed now. All the New York City homes were plumbed in copper.

schooncw · Dec 7, 2016

I have been using Toronto tap for 3 years, since I moved and my tank has never been better! I do run PO remover and carbon 24/7.
If it's just a nano, why not just buy prepared RO water?

Reeftang · Feb 25, 2017

Paul B said:
I used NYC water for about 20 years or so and NYC had some of the cleanest water in the country because it comes from upstate reservoirs which are about 22 miles from the city. The tunnels were built out of cobblestones well over 100 years ago and run 900 feet below the city. The problem is that a few years ago we opened up one (or two) of the new water tunnels as the old tunnels probably leak more water than they carry. I was in the new tunnels and all that construction debris, metal, chemicals, dead pigeons, frankfurters and other stuff that comes off new concrete will infuse into that water for the next 100 years so it is no where near as good as it was. You could use it of course, but you may have some problems.
By the way, the NYC water tunnels were the longest tunnels in the world until they built the "chunnel" between London and Paris.
I think the copper in New York City water comes from home plumbing because PVC plumbing was always illegal here, I am not sure if it is changed now. All the New York City homes were plumbed in copper.

Have you used this water to keep corals???

Paul B · Feb 26, 2017

I don't think so. They didn't keep corals for the first ten years or so when I entered the hobby but I am sure you could potentially have problems with corals. In any case, the tap water won't make it easier. But I did filter the tap water through a pipe filled with carbon. If you really need to use tap water, at least filter it through a 4' 2" pipe filled with carbon a couple of times.