Ro/di questions

APrince62 · Dec 9, 2018

Still gathering equipment to start my 75 gallon SW tank....did get my 125 G tank today to move my FW fish into. When hubby saw how big the tank was he asked how in heck I was gonna fill it.....told him treated tap water to start then bottled water after that. He immediately said you need a water system. ......so I’m now looking for a ro/di system ....now for questions....
1. Can I use the water for both FW and sw tank?
2. Am I just filling holding containers with water to be used?
3. Can I get an acceptable one on amazon?

cromag27 · Dec 10, 2018

APrince62 said:
Still gathering equipment to start my 75 gallon SW tank....did get my 125 G tank today to move my FW fish into. When hubby saw how big the tank was he asked how in heck I was gonna fill it.....told him treated tap water to start then bottled water after that. He immediately said you need a water system. ......so I’m now looking for a ro/di system ....now for questions....
1. Can I use the water for both FW and sw tank?
2. Am I just filling holding containers with water to be used?
3. Can I get an acceptable one on amazon?

1. when i kept fresh i would ro water. saltwater should always be rodi.

2. yes.

3. yes, https://www.amazon.com/gp/aw/d/B009...ure+maxcap&dpPl=1&dpID=51-3HKnkJ1L&ref=plSrch

but this is cheaper, https://spectrapure.com/RO-RODI/RODI-SYSTEMS/MaxCap-Standard-90-GPD-RO-DI-System

SPR1968 · Dec 10, 2018

RODI water is one of the basic requirements for a Marine tank, like up there with the actual tank. Only ever add water at 0 TDS and your off to a good start.

Yes you can store the RO water and the units aren’t that expensive in the scheme of things as already shown above.

And welcome to R2R as well!

kiMxD · Dec 10, 2018

Zero TDS is the best practice, however, TDS’s up to 3 had been noted to be okay.

cromag27 · Dec 10, 2018

kiMxD said:
Zero TDS is the best practice, however, TDS’s up to 3 had been noted to be okay.

uh, noted by who????????

kiMxD · Dec 10, 2018

By fellow reefers, google it up

I personally ran my system for over a month with a 4 TDS until I could finish my cabinet. Nothing went wrong during this time and I have swings of 0-1 all the time.

Gsxrfl1k6 · Dec 10, 2018

Check out BRS, they have a pretty good range for all price points, etc. Also have some good vids on the topic.

APrince62 · Dec 21, 2018

Ok have system on way....next question......how do I get water from storage tubs to tank??? The thought of filling, carrying and emptying 5 gallon buckets one at a time to fill a 75 gallon is pretty daunting. what am I missing here?

cracker · Dec 21, 2018

Welcome to R2R APrince !

Tastee · Dec 23, 2018

For your FW system you need to be careful using RO or RODI, particularly for a planted system, as a lot of the material you strip out is actually useful for a FW tank and plants. If you only use RO or RODI you will not be able to keep plants alive. You will need to add back in the beneficial material via additives.

This is of course exactly what we do in a SW system, it is just less common to do this in a FW system as starting with pure water simply isn’t as important. You typically won’t keep invertebrates, so free Cu isn’t an issue for example. Chlorine is the only real contaminant you want to avoid and that is easy to remove.

If it were me I would start by understanding a little more about what is in your tap water - what is the TDS, what type of treatment does your town supply do etc. If the answer to this is high and lots of nasty stuff (like chloramines) then RO or RODI water may help. I don’t it myself but others use a mix of tap water and RODI water, say 50/50.

In my case our tap water is ~75 TDS and the treatments used are not a big concern so I just use tap water in my planted FW tank, and RODI for top ups. My son however is keeping FW Shrimp and plants, so uses RODI, runs a CO2 system and adds plenty of additives to give him the water conditions he wants. I definitely get a little more algae in my tank than he does, but nothing that isn’t easy for me to manage and not unsightly.

Without knowing much about your tap water, if you want to try it, perhaps start with 50/50. If you find the plants aren’t growing, reduce the RODI percent. If they are growing but you still have more algae than you want, increase the RODI percent.

Using RODI for top-up is not an issue, as it is really only pure water that evaporates.

Good luck!