Beginner/Used RODI unit.

[Mjk412]

I'm brand new to the saltwater hobby. I've kept freshwater for 10 years. I have a empty 75g tank that I'll be using for my saltwater setup. My first purchase is going to be a good rodi unit. Here is where I have a questions.


A cowoker gave me a 4 stage rodi unit for free. 3 large filters on the bottom and one on top. He doesn't know anything about this system. The brand is Kent Marine HI-S Maxxima. It's a bare bones system. No pressure gauge and tubing needs replaced.

How can I figure out how manny gallons this unit will do?
How can I upgrade this unit to make it really good?
Is it worth upgrading? Since I wanted to add a pressure gauge, tds meter, flush system. Not sure what else I'll need.
Or should I just buy the refurbished Spectrapure 90G per day system for $180?

Thanks so much everyone.

 

[flooddc]

I used to have one.
I believed it's up to 75GPD depending on the membrane installed (the one on top).
It's perfectly fine to use it and add some upgrade to it. You can even upgrade to the 150GPD with the BRS upgrade kit.

You will need to replace all filters and a new membrane.

Auto shut off is a must!

 

[Mjk412]

What is auto shutoff?

 

[Mjk412]

The unit does not even have any tubing on it. I would have to figure out what lines go where.

 

[flooddc]

What is auto shutoff?

It's shutoff when your water reservoir is full. I flooded my basement 2 times without it and once with it due to human error.
BRS sells the auto shut off kit for $25.

 

[flooddc]

The unit does not even have any tubing on it. I would have to figure out what lines go where.

There is a diagram somewhere here or online. I think video too.
appeared very complicated, but it's really simple.

water enter into first canister (sediment); out of first canister to 2nd canister (carbon), out second canister to membrane; 1 out of membrane to third canister (DI risen); 2nd output of the membrane is waste water; out of third canister to reservoir.

Post pics so we can walk you through it.
Once you get the basic setup, you can add the pressure, auto shutoff, tds, etc.

 

[flooddc]

Typical Diagram;
https://blog.marinedepot.com/educat...everse-osmosis-deionization-rodi-system-works

this looks like your?
https://www.youtube.com/watch?v=UVC7_xoVHKU

 

[Mjk412]

Thanks for all the help! Now what filters should
I buy? It’s for a 75g tank. Do you think it’s cheaper to upgrade this one or just buy a new unit for $200?

 

[jamie1981]

Thanks for all the help! Now what filters should
I buy? It's for a 75g tank. Do you think it's cheaper to upgrade this one or just buy a new unit for $200?

That's probably a toss up. The most expensive part of a ro/di unit is the filters themselves. By the time you buy the filters and add on's separately your probably going to spend the same amount or more than a new unit.

All you really have is the shell to the ro unit. The housings are all basically the same other than some are clear and some are not.

 

[tkeracer619]

It really depends on your source water. Are you on well water? City water with Chloramines? High Silicates?

Certainly would help to know where you get your water to take a gander at the water quality report (if you are on city)

 

[Mjk412]

It's city water.

 

[flooddc]

Most expensive part of the RODI is the membrane $40 (but lasted 3-5 years depending on water source).
$30 for replacement filters. (you can buy bulk and it's a lot cheaper!)
https://www.bulkreefsupply.com/brs-...MIws3Ajvqb2QIVxFYNCh311QfIEAYYASABEgIWu_D_BwE

When I first dived into reefing, I have no idea what's the RODI is, bought a used one and was overwhelmed. I didn't even know about reef clubs until a few years later. I learned and make many mistakes along the way, but you learned for mistakes.

Anyway, it's really up to you as to whether to buy a new unit or work with what you have. To me the RODI are pretty much the same regardless of brand. However, some have better quality than other.
Since you're using city water, go with a 5 stages unit such as this if you want to go with the new unit.
There are a bunch of vendors on here as well.

https://www.bulkreefsupply.com/5-stage-75gpd-plus-ro-di-system-bulk-reef-supply.html

 

[tkeracer619]

It’s city water.

This means nothing. Please give actual specific details, like where you live and who you send money to for water.