Question about RO water versus other sources...


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Oct 8, 2020
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Port Orange
I keep getting different answers depending on whom I ask. If I don't want to go to my LFS and trudge home with RO water in a bucket what sort of alternatives do I have? I google it and have read where you can use Purified water, or distilled water. Today here in Daytona I went to another fish store as my usual one is closed on Monday and the guy there told me you can either use purified water or even bottled drinking water, since its only used to top off the tank after evaporation.

Still not sure what to do..
Lazys Coral House


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May 15, 2020
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Western Australia
Long term you are simply better off with your own unit, i purchased one that i can make drinking water from the RO side and then make my 0 tds for my top off with 3 tds metres to show water in, water out after RO unit and water out after DI unit. I bought a custom unit, depending on your area and your water supply, you may not need a 6 stage, all that can amount to is more resin to replace after its depleted, i just bought extra DI resin, carbon and poly pre filter for my service schedule instead.
While i count myself lucky that i do not need to make ASW and use NSW for WC, having your own RODI if you cannot get get NSW due to geographical location is the best thing you can do for your wallet, yourself and your display long term.
i know for me the investment is by far worth it with what i am saving in drinking water filters, trips to the LFS where they only make 30tds anyway and charge a dollar a litre for it as my evap is around 8 litres per day.
Top Shelf Aquatics


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Oct 13, 2017
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ah more sound advice from your friendly LFS....ok here's the principles evaporation occurs, only pure water evaporates...leaving behind the salt, minerals, trace elements you need to replace that with water that has no extra stuff in it...if you replace it with tap water, well water, spring water, bottled drinking water , etc the additional elements present in the top off will slowly build up in the system and depending on what compounds are present can cause any number of problems in your system...algae blooms, diatoms, fish and invertabrate deaths....drinking water varies greatly all over this country depending on its source but whats considered safe to drink can have any number of things in it that aren't good for your tank...i'd be very interested in what the definition of "purified " water through a carbon block and chlorine added to kill bacteria? distilled water can be used (heard rumors of trace copper from distillation piping) but in reality is dragging home bottles of distilled water from walmart or the supermarket any less annoying then dragging it home from a LFS?...when covid initially hit every store around here was sold out of any kind of water...and i've been to my lfs when they were sold out of RO/ its nice to be in control of your water needs


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May 14, 2018
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What snorkl said.
It's so annoying to have to save up and buy another piece of equipment that's boring compared to the fun stuff like livestock but it's definitely a wise investment.
In the meantime keep lugging bottles- that's what I did in the beginning many moons ago- deionized water from publix lol

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