Tap Water?


Active Member
Not a good idea...Tap water has to many chemicals in it.
The very least you should use is distilled water, but the best would be RO/DI water. :D


I used tap water to fill up my 60gal at the begining. Then i used this chemical to get rid of all the harmful chemicals. Then i used RO/DI water for water changes.


tap not only has chemicals, but other problems. it probably has nitrates to start with. it also probably has phosphates. nitrates are what ur trying to reduce with water changes. phosphates can lead to problems like cyanobacteria.
start by contacting ur water supplier. by federal law, they have to test for chemicals and tell u what ur drinking. ask about all the things we normally test for.
i gotta tell u tho, i invested in a RODI filter. cost me $160 and (IMO) was worth every cent. i havent had NEARLY the problems i used to have with other tanks in the past. (algae, etc).


New Member
If your setting up a fresh water tank I'd go with tap water and I would still use tap water if you only plan on only putting in clown fish or damsels but if your going to go with a reef tank I would try to go with RO unless your water TDS shows under 250



Originally posted by chriscobb
Big911 is right!!!!! My water company sends out reports every so often to let you know what they test and what the results are. I would just contact them out of curiousity.
As for Madysmom I'd say you must have very good water quality to begin with??? Do you test for TDS on your tap water????? What are you keeping in your tank???

as for the TDS i havent ever checked it
I have a 29 gallon sw tank with
1 rusty angel
1 percula clown
1 mandarin dragonette
1 yellow tail
2 peppermints
2 sexys
2 rock flower anemones
2 zoanthid polyp frag that are getting bigger every day!
some hermits and snails
i have lots of life and find new growth in my tank everyday, oh i have some rocks with some pretty coraline(green, turquoise, pink, maroon, purple, white)
i have heard of lots of people who dont use tap but my sister uses well water and her tank is fine too. i guess we are lucky! :)


Active Member
For reef systems, it is absolutely neccessary to use RO/DI because of the chemicals in tap water, but for FOWLR systems, you can get away with using tap, just as long as you either 1) don't mind the algae that may come with it, or 2) run some sort of phosphate remover, such as Rowa-Phos.