RO water or tap water?

Fishy01

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Do you have to use RO water when setting up a saltwater tank, or can I just dechlorinate the tap water and use it? I use tap water for my freshwater 60 gallon with no problems.
 
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melonheadorion

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i personally have used tap water setting mine up. gotta dose it with dechlorinator, but it will work. i never ran in to algae issues other than the standard uglies that everyone gets, but that went away. on the other hand, tap water can vary. well water has different elements than city water, and cities will have different elements between them.
it can be used, but many people will say it is best to use RODI water because all of that gets removed through the filtration process. you can check your water departments readings. they are required to publish them. one thing you will find is that water contains trace elements of stuff that will scare even you, such as cancer causing things. if i recall right, my water department acknowledges that there is hexavalent chromium within it
 

NeonRabbit221B

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Please point me in the direction of a 5 year old tank that runs on tap...

You don't know how what is in your source water or the rate that those things will accumulate with evaporation. You will have enough issues in a new tank before you tack on those that will come about from using tap. Just don't do it.
 

Gtinnel

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IMO you may be able to get away with tap if the tank is FOWLR but not for a reef. However, I would strongly reccomend only using rodi water. Compared to the cost of everything else in this hobby a low end rodi filter is not that expensive.
 

WVNed

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If you put tap water in your system it concentrates all the impurities over time. The water evaporates away every day and you add more tap water to replenish it. You are adding more of the impurities in the tap water every time you do. The impurities never leave the tank and even if you have very good tap water you will eventually have problems you cant fix.
 

LordofCinder

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if you want a fish only tank it could work with tap, but most eventually want corals or anemes or invertebrates, which are all sensative animals. The cost of running a reef tank is incredibly much more than running a freshwater tank, in the long run it doesn't make sense to cheap out on $150, just my opinion
 

1ocean

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Please point me in the direction of a 5 year old tank that runs on tap...

You don't know how what is in your source water or the rate that those things will accumulate with evaporation. You will have enough issues in a new tank before you tack on those that will come about from using tap. Just don't do it.
ok hahahah i am pointing to a 5 year old tank that runs on tap water------> all dead, dried out and in the garbage can..
 

Randy Holmes-Farley

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Do you have to use RO water when setting up a saltwater tank, or can I just dechlorinate the tap water and use it? I use tap water for my freshwater 60 gallon with no problems.

No one can say whether you can use tap water or not, because it depends on what is in your tap water. Even if your neighbor uses it OK, you may not be able to due to your own pipes releasing copper (or not).

Tap water works fine for some, and would be a coral killer for others. Copper is a big concern.
 
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srobertb

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Can I do water changes with tapwater
No. No tap water. Ever.

You’re going to have so many problems with your tank. Using tap water is going to add to the long list of problems a novice and a new tank already have.

Buy premixed seawater from a fish store (Petco carries it too) and use distilled or purified water from the grocery store until you can buy an RO/DI unit.
 

reefingaz

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Ok my friend, lots of comments and lots of opinions About this topic. Setting up a proper and beautiful reef tank could cost you thousands of $. Yes many can do it and have done it for less trying to cut corners- aka using tap water.
Those are the same people on here posting that their tanks look horrible, phosphate is thru the roof, can’t keep anything alive, corals have no color or won’t survive. Somehow these people have become experts. I’m sometimes shocked and disappointed at some of the recommendations that some “experts” post on this site. To hear “you will be fine using tap water on a reef tank” is the same guy saying you can load up your tank with corals after 1 day of setting up and no cycle is needed and oh yeah, you don’t need no stinking bacteria in your tanks!
Please do yourself a favor and Invest
In an rodi for your tank. In the long run it will be WAY cheaper than the corals and lights you plan to buy, but JUST as critical for keeping your tank alive and looking great.
FYI here in AZ my tap water is “super clean” to the naked eye. It comes in at 545, yes 545 TDS and my RODI takes it down to Zero! That type of high TDS would never support my high end corals.
Best of luck.
 

HawkeyeDJ

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If you put tap water in your system it concentrates all the impurities over time. The water evaporates away every day and you add more tap water to replenish it. You are adding more of the impurities in the tap water every time you do. The impurities never leave the tank and even if you have very good tap water you will eventually have problems you cant fix.
^^^^^ THIS! ^^^^^
 

WVNed

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I sensed war when I clicked on this…
Why war? People have every right to screw up their own tanks. I used tap water. I screwed up my own tank.

Now I don't anymore. If you do this long enough you will know why not to use tap water. Then you will start over or quit.

I started over.

All you can do is tell them why not to use it.
 
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