Distilled water vs RO

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NCStateFisher

Polypterus
MFK Member
Sep 27, 2010
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I know that RO is best for salt tanks but I was wondering if distilled works okay, mostly for an initial fill. I'm starting a 20 gallon long salt tank at some point next month and just trying to figure out all my options before i put all this in to action

thanks
 
usually ro water is also distilled so i would say its fine. spring water would also work. just check for phosphates.
 
I would watch using spring water, some of the "springs" they use have nitrate or nitrite. as humans we can handle alot more as "drinkable water". I've test a few brands of spring water some are good others very bad (aka i wouldnt let any animal drink it, much less live in it). I would test any water source before use unless you know its coming from a working ro unit.
 
this is true.. i use spring water for my brackish tank. it has no nitrates or phos. some may have more then u want. i guess distilled may be a better choice.
 
What type of salt water are you thinking?

Reef or FOWLR?
 
At the same point you can honestly buy premixed RODI sw for 1.00-1.50 a gal... I mean your looking at spending a whooping $20... i would rather do that an mess around with spring water etc.
 
What type of salt water are you thinking?

Reef or FOWLR?

I'm doin FOWLR for now until I get used to it. And yeah Tmartinez i know long term i'll be using RO i was just thinking that I might use distilled for my initial fill so that I have the big water jugs to get RO in the future lol
 
Hmm for FOWLR, I believe you can use tap water.
Though it is not recommanded if you are keeping sensitive fishes and would most likely cause algae bloom.
Best would still be RO/DI water
 
Is there anything wrong with your tap water?

I use mine for reefing.

You should have it tested for heavy metals, chemicals, nitrogenous wastes, and phosphates.

If you dont have any of those, your water is more than suitable most likely even for a reef application.

Again, professional grade testing is key.
 
+1 to the above

I live in a city with excellent water quality. I personally know a few people using tap water for their reef tanks. Everything in the tank is thriving and healthy. I use RO water but that was mostly because I found a great deal on a RO unit. As Fleshy suggests, get your water tested to make sure befor you use it, or use RO water.
 
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