Do you use tap water for your marine tank?

Do you use tap water in your marine tank?

  • No, never

    Votes: 11 36.7%
  • No, I tried it once and it wasn't a good idea so I went back

    Votes: 3 10.0%
  • Yes, it works good enough I guess

    Votes: 8 26.7%
  • Yes, and never had a problem with it

    Votes: 8 26.7%

  • Total voters
    30

Sploke

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Oct 20, 2005
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Matt
Just wondering how many of you buy RO/DI water and how many just use tap water?

Also, if you do, can you post your tap water params, well/city water, etc?
 
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As low as ~10 ppm on the TDS meter on a good day.

I don't use RO/DI because it's of significantly better quality than my tap water (it's not), but for the consistency and knowing exactly what's going in the reef tank.
 
I have been using tap water and I've been having PH problems since I started the tank. Well I finally used and completed my calcium test kit - and it turns out newly mixed saltwater comes out with an unreal amount of over a 1000 ppm of calcium, so the next water change is being done with bottled water.

I can't vote - none of the poll options describe my situation.
 
The part I'm not getting is that I keep seeing when you do your water changes, it's not to get the crud out of the sand it is some for nitrates and to replenish minerals. IN RO/DI there are no minerals, so where am I missing a link? I would prefer to use tap the parameters stay pretty stable.
 
well, saltwater mixes contain a lot of the minerals you need, some brands more than others. You might have to end up adding a little liquid calcium or something like OSMO Prep Marine to boost specific minerals, depending on your tank's chemistry needs (FOWLR vs. reef for example).

If you have no sensitive fish or inverts, and good filtration, anything extra from your tap like ammonia/nitrates or phosphates probably won't hurt you. Those levels shouldn't be through the roof (otherwise we wouldn't want to drink it either) and your system should be able to deal with them.

Someone correct me if I'm wrong :)
 
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I use RO water because I get it free. Our well water has traces of lead, so the town supplies free bottled water. 25 gallons every couple of weeks, which is plenty for my 29. I don't see any reason not to use it, you know exactly what you are putting in.
 
I use tap water with a fowlf setup and everything is healthy except my nitrates are through the roof at about 80 ppm, which causes excessive algae growth. Other then that problem, everthing else is healthy.
 
Tap water caused too many algae problems so I switched to DI water and the results are much better in my reef.

Marinemom
 
My water comes from a well, and it works just fine. I can get away with throwing freshwater fish directly into it without adjusting the PH. When I place it in my marine tank, I use a buffer to raise its PH and hardness.
 
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