Tap water for a mixed reef??

[ReefGuy1234]

I used to make my own RODI water at 0 tds. Something happened to that system that is a story for another time. I purchased RODI water from my lfs and the TDS WAS AT 550! My tap water is at 60. Also that’s the only lfs near…

So what is so bad about tap water? Other than the chloramines, chlorines, heavy metals, wack pH, phosphate and etc. Can those be exceptions when well dechlorinated? What are the real negative effect from tap water?

 

[Mr. Mojo Rising]

"dechlorinated" removes only the chlorine, all the other things will be in your system, and build up over the years. Some may possibly be absorbed into the rocks, compounding the buildup.

 

[PatW]

I would not use tap water. Tap Water often has copper in it and that kills inverts. Also tap water can have nitrates, phosphates, heavy metals, pesticides etc. Get an RODI system. If $ are a big issue, just use an RO system, that will remove 98% of the crud. But given the cost of reefing going RODI is the way to go. It is cheap insurance.

 

[CoastalTownLayabout]

Pros and cons should be determined by what type of reef you are trying to manage. Hobbyists who’ve been in the game for 20+ years know that RODI systems were pretty much unobtainium back then but still kept beautiful soft and LPS systems. Nowadays though, if I was running a high end SPS or LPS system, there’s no way I would consider not using RODI. You cannot match the consistency of input provided by a well maintained RODI.

Personally, I have used collected rainwater and NSW for my reefs over the last 15 years with no problems. I’m not an SPS guy though so every decision should be situational.

 

[homer1475]

Tap can also cause all sort of alkalinity issues.

Copper pipes in the home is another issue.

I used to use treated tap. As said above, 20 years ago we didn't know any better. As long as you know whats in your water(read your towns water report), and can adjust for whats in it, I see nothing wrong with it.

 

[bushdoc]

I used to make my own RODI water at 0 tds. Something happened to that system that is a story for another time. I purchased RODI water from my lfs and the TDS WAS AT 550! My tap water is at 60. Also that’s the only lfs near…

So what is so bad about tap water? Other than the chloramines, chlorines, heavy metals, wack pH, phosphate and etc. Can those be exceptions when well dechlorinated? What are the real negative effect from tap water?

Your Department of Public Utilities publishes water tests/ parameters, usually yearly. I suggest looking there. Small amount of impurities will eventually add on as you are topping of your evaporated water with tap water.

 

[mdb_talon]

So what is so bad about tap water? Other than the chloramines, chlorines, heavy metals, wack pH, phosphate and etc. Can those be exceptions when well dechlorinated? What are the real negative effect from tap water?

That's the key questions right? There are countless thing that could cause water quality issues....especially over time. You can usually get a local water report and find out exactly what's in your tap.....based off that given time the sample was taken. However that does not tell you what it's going to be in three months. It doesn't tell you if there is a leak letting impurities in somewhere along the line. It only tells you what was going on when that sample was taken.

I guess my point is tap water can be used and sometimes very sucessfully. It's also a risk because of all the unknowns(or future state unknowns).

As others said many of us used to use tap water many years ago. However I would argue that there was a lot more failure in the hobby then than there is today and I would bet that water is one of the factors.

 

[bushdoc]

That's the key questions right? There are countless thing that could cause water quality issues....especially over time. You can usually get a local water report and find out exactly what's in your tap.....based off that given time the sample was taken. However that does not tell you what it's going to be in three months. It doesn't tell you if there is a leak letting impurities in somewhere along the line. It only tells you what was going on when that sample was taken.

I guess my point is tap water can be used and sometimes very sucessfully. It's also a risk because of all the unknowns(or future state unknowns).

As others said many of us used to use tap water many years ago. However I would argue that there was a lot more failure in the hobby then than there is today and I would bet that water is one of the factors.

Yes, you can use tap water successfully, unless it is from Camp Lejune or Flint, Michigan or many other places like some in Central Valley, CA.

 

[CoastalTownLayabout]

Interesting point, incidence of failure in the days when RODI was not widely available. I don’t recall it ever being a commonplace issue. I do recall the effort being towards nutrient reduction though with GHA and bryopsis being the often cited consequence of failure.

Pivot to today and low nutrients seems to be the common fail point, especially dinoflagellates. It seems to be accepted that dry rock is the culprit but I’m not sure this is the whole story.

I’ve found that using RODI results in too lower nutrients for my systems and have battled dinos only when using it. Rainwater has been the sweet spot for me.

Again, must emphasise that I do not keep SPS dominant systems.

 

[Danny G]

Best thing about RODI is you know exactly what you are getting each time. Tap water has all sorts of minerals and other compounds that can be very damaging to corals. Tap water can cause domino effects in a reef tank with algae breakouts among other issues.

 

[Sleeping Giant]

if tap is your best option then in my opinion it's worth a shot, I used tap for 7 years with off and on results. I switched to RO and it's better, next I'll upgrade to an actual rodi system and call it a day lol

 

[vetteguy53081]

Its NOT worth it. With so many sales on RODI units- worth the now small investment.
For starters, the amount of Alk in tap water can potentially double this number easily and affect CA and PH not to mention content of heavy metals, chloramine, polluants. flouride and other elements not contained in sea water. tap water also offers no ph buffering and note many areas have copper in their taop water which you do not want in your system. Next will be phosphates in water which will cause further issues.
As you can see - Risk is the issue

 

[ReefGuy1234]

Thank you all so much for the amazing answer. I think my best option is to try and fix my RODI situation into which I was going to get to eventually but as of now I need something temporary. The RODI unit I have works great, and it’s one from BRS and does 0 TDS water. Like I said there is a whole situation with the RODI that is irrelevant to fish and is a problem I need to fix. Once again thank y’all.