Can you get by with an RO only unit?

[shollis2814]

So, I have been getting water from my LFS. I vary between 5-15 gallons a week of fresh/salt. It's a 36 gallon tank with sump (about 40 gallons total).

I have thtought about purchasing a unit and setting something up under my house to mix my own water, but I cant' swing a full RODI unit right now. I do see some affordable RO units.

Would that be dependent on my local water? How vital is the DI portion? I'm thinking I just need to keep buying LFS and hope Santa is good to me this year.

 

[happyhourhero]

Usually the DI is to finish off the remaining TDS after RO. Depending on your local water, you may need it to get 0 TDS. I have a cheap RO buddie with the DI from amazon and it does just fine. People that spent way more money will hate on it though.

 

[sbash]

I did for about 6 months without any real issue. Until my sump cracked and I had to replace it and 50% of my water volume. Half my livestock died as a result (not right away, but it took me a couple weeks to find the source). The forum I frequented at the time just constantly flamed me, telling me my system was not cycled and to do large water changes to get the levels down. That only made the problem worse. Had I tested my tap water and the product water from the RO system, I would have avoided those issues...

It turned out the RO system was not able to fully remove all the ammonia from the source water (city water). So to quote Reverend Lovejoy: Oh, short answer, "yes" with an "if." Long answer, "no" with a "but."

Get the RO system, but make sure you test your source water, and the 'finished'. Add the DI as soon as you can...

 

[Untamedrose]

A just RO will not remove chlorine and chloramines. ...It WILL need to be treated for such.

It's better then tap but...

 

[twilliard]

A just RO will not remove chlorine and chloramines. ...It WILL need to be treated for such.

It's better then tap but...

The carbon block in the ro will remove this

 

[jason2459]

Some people have used straight tap water for years with no issues once the chlorine is neutralized. Some people can't. You really need to know what's in the water and know when it changes as water quality and treatments change periodically.

I have around 9 tds after RO and before DI. However, its practically all copper so I have to use DI. TDS is not a good indicator of water quality. 1 TDS could kill and 100 could be harmless. You need to know what is in the water. Then there are times when the local utilites will treat the water or pipes and you wont know it until your tank reacts negatively as what could be used for treating is considered perfectly fine for human and most animals but not marine life. Then there's the sporadic and uncommon events which require boil orders but may be to late before that order goes out and your tank is nuked.

And then there's Flint Michigan.

 

[redfishbluefish]

My opinion...do it right!!! HERE is a great unit for $125.

 

[AZDesertRat]

RO acts as pretreatment for DI, by itself RO would only be 90-98% efficient. There are also things RO is not particulary good at removing without DI such as nitrates and all forms of ammonia, silicates and phosphates.
If it is worth doing, it is worth doing right the first time.

 

[shollis2814]

Thanks for all the input. Looks like I need to save up for the full unit.
Phosphates are really high straight out of the tap here in Nashville. thanks for the recommendation @redfishbluefish . I'll put that on the wish list.

 

[jason2459]

The unit itself is pretty universal as well as the sediment and carbon filters. Bulkreef, spectrapure, buckeye hydro, etc will all do just fine.

As for the membrane I feel that spectrapure sells some of the best.

 

[Sabellafella]

So, I have been getting water from my LFS. I vary between 5-15 gallons a week of fresh/salt. It's a 36 gallon tank with sump (about 40 gallons total).

I have thtought about purchasing a unit and setting something up under my house to mix my own water, but I cant' swing a full RODI unit right now. I do see some affordable RO units.

Would that be dependent on my local water? How vital is the DI portion? I'm thinking I just need to keep buying LFS and hope Santa is good to me this year.

Take a look on a local forum, in sure you can find one for 50 buckaroos somewhere

 

[AZDesertRat]

99 times out of 100 when you buy a used RO or RO/DI you inherit someone else's problem. The $50 you spend will quickly exceed the $125 you would have spent for a new high quality RO/DI.