Has anyone tried a long term experiment using tap water vs RODI water for a reef tank?

[GARRIGA]

Some trace metals do seem quite high.

Yet relative to what was in my tap not sure if just missing in that sample or if some being consumed by the algae yet not fast enough. Here's my tap water analysis isolating only those items of concern.

Over the course of two plus years I'm estimating I replaced about 50 gallons of evaporated water with tap. Absent the water change. Was assuming these should be considerably higher. Thinking algae might have utilized some or I'm just not understanding what levels I'd have after that much replacement with tap.

 

[GARRIGA]

Isolating on aluminum. I have only three times the volume from the tap sample. Shouldn't that be considerably higher unless something was removing it? At a minimum. Rather confident my pumice isn't leaching excessively to the point I shouldn't be using it. Tank had 1/4 filled with it.

 

[Randy Holmes-Farley]

All organisms use trace elements, though some may get it from foods as opposed to the water. It is certainly to be expected that these decline, both from consumption and precipitation.

 

[TeamAquaSD]

Yes, it was called the 90's

All about that well water haha

 

[MnFish1]

The TDS for the tap water in my town is ~60 which is great for tap water so I thought “why not” and that’s how I filled my first reef tank. I’ve been using treated tap for a long time with fresh water tanks and I have ultra clear water and an almost self maintaining tank.

Enter the reef tank and ugh… lesson in humility. The amount of hair algae was just insane. While some LPS did really well, gonis for some odd reason did awesome in that tank, others did not… torches would wither away. Duncans loved it. Acans did well. My red fire Digi did okay. The rest of anything SPS that I tested would usually be okay for a day or two and then STN would kick in. The phosphates were always at 5 (yes 5, not 0.5) or above and the nitrates were 20-60. Stability was nonexistent.

The only difference between how I run my current system versus how I ran my previous system: you guessed it RODI instead of tap. I guess I also carbon dose now which I did not do from the beginning with my previous tank.

Just my experience. I am sure some tap water out there can support a reef tank without causing issues, but I also know that few sources are likely to.

Actually - my guess would be that many tanks may be ok with not using RODI - however, its also possible that the water guys will add chloramine, or something else - which can cause problem. RODI does a nice Job removing doubt about what might. be there/not be there. IME

 

[MnFish1]

Unfortunately I’ve lived in some of the least desirable places in Rhode Island (South Providence, Chad Brown, Pawtucket,Woonsocket) If you’re from the Area or surrounding states you know what I’m referring to….. I’ve also lived in the white mountains of Nh. As well as the south shore of Massachusetts.
All the while keeping and maintaining a thriving ecosystem. I have never used RODI water, using strictly tap water every place I go. Never running into any issues…

I could be entirely wrong, however the way I look at it is an immune system for corals/fish/inverts. I feel as if you only use RODI water they will become less tolerant of anything in your aquarium. Where as if using tap water they build up an immunity to all sorts of stuff.

All this technology has come about recently making people believe you need a degree in chemistry to keep a reef tank…. People are also under the assumption nano reefs are harder to keep and more susceptible to failure.
Without a calcium reactor, doser, sump, UV sterilizer, ATO or anything fancy. I have sucessfully kept and maintained Nano tanks for 12 years now. All I do is keep a 1 gallon jug of water that I fill up with tap water. Keeping an eye on my water level I try and add a half gallon at a time. With weekly or biweekly water changes, again, using tap water. I have never had any issues. <——just my two cents!

I don't agree with this plan without a test of the water (or at minimum, a look up of the various items in the water). I do not think using tap water influences the immune system unless there are toxins present. It also depends on what's in your tank, i.e. bioload, etc etc etc.