Best RO unit for 300gpd production?
- Thread starter Dmorty217
- Start date
Dmorty217
Saltwater Addict
Closer but not where I would like to be. We are getting ready to move in the next month or two then I will be feeling a lot better about having the tank running by this summer. I need a basement with equipment room and water supply and drain in the floor for accidents and easy water changes. Did you get the 200 gpd membranes or the 300 gpd to get the 200g of RO? All of these RO systems measure output at 77 degrees and my cold water feed comes out at 57 degrees right now. How do you do it, out of a faucet hookup? Otherwise I don't understand how you achieve 77 degree water flowing thru the RO?
SPotter
Active member
I have the 200 gpd membranes. Ive never paid attention to the water temp going in. The fish room I built is in my garage and when we were building the house I had the plumbers put a hose bid faucet where I would be building the room....they all thought I was crazy. So I just hook the unit up to that with the adapter and run it from there. I have never tried to figure out if I am getting 200 gpd or not but I think I am pretty close to it based on how long it took to fill the tank.
FuzzyZipperbaum
New member
There are a few good ones out there... I use maxcap 200gpd for my 1200g system. The key for me was not the 200gpd but the booster pump. When I added the BP not only did I get better water production, but I also got less waste water and used less media.... My normal water pressure is ok but there is no way I would do a RO/DO without a bp unless you have insane water pressure already...
Dmorty217
Saltwater Addict
Thanks for the info. I figured that most of us have our RO units hooked up to the cold water supply under our sinks/in our homes but I was speaking to someone about thier RO units and this one in particular was for 300gpd at 77 degrees and the guy mentioned that for every degree below that the less the RO unit will make and recommended a 600gpd unit to do 300gpd at 57 degrees. Then it got me thinking that unless we hhow them up to a facet that no one is achieving 77 degree water to thier RO system. Plus with the logic I was told then I should really be looking at a system that will produce 1000gpd. I would rather no spend 1k on a RO system. After this I need some sand and salt and a new home
Dmorty217
Saltwater Addict
I'm about a mile from the water tower so I would assume I'm getting good pressure but I have never checked
Vinny Kreyling
Premium Member
In the old house we had 45 PSI & the RO production was fair.
Added a booster pump & production went up 1 GPH with 90 PSI.
New house is 80 PSI so I sold the pump.
I realize you will have a lot of water but do you really need it so quickly?
A large holding tank might be better. I can make 50 gallons in about 12 hrs in the winter, so @ 100 GPD, in 2 days you could do a 20% water change.
I cheat a little with an inline water heater I made up.
Added a booster pump & production went up 1 GPH with 90 PSI.
New house is 80 PSI so I sold the pump.
I realize you will have a lot of water but do you really need it so quickly?
A large holding tank might be better. I can make 50 gallons in about 12 hrs in the winter, so @ 100 GPD, in 2 days you could do a 20% water change.
I cheat a little with an inline water heater I made up.
Dmorty217
Saltwater Addict
I have a 150g holding container and a 330g holding container, so holding the water isn't a problem. The problem is I don't want to have to turn on my RO for a week to fill the tank and if I have something come up unexpected I want the ability to make close to 1/3 of the total system volume in a 24 hr period. The RO unit I currently have has a lot of rejection like I mentioned I don't want to have to leave the RO system running continuously to have top off water and water change water. My 100gpd does about 60 gpd now since it's winter and my water is 57 degrees and I don't know what the psi is. I'm just guessing but I'm assuming that I will have anywhere between 60-100g per week in evap (have between 20-25 now in my 250g system) plus the QT system will have a auto top off with somewhere around 100g or so between the two tanks (I have a 75g and will also hookup a 20L or 40g breeder) so we will say 100-120g per week in top off water plus water changes of at least 200g at a time, 300g each water change would be better. So you can see that if I don't get a RO that will produce some GPD that I would literally never turn the RO unit off
SPotter
Active member
when I was shopping for a new rodi to go with this set up I spoke with one of the popular online vendors who I will keep nameless. They sell various brands and I was asking about whats the difference from one to another and they said that hobbyists get too caught in the rodi equipment and then cheap out on the replacement filters. They said that for the most part all of the equipment is the same with some minor differences with booster pumps or auto flush features. I was all set to buy another more expensive brand before I had this conversation and then decided on the Aquafx which still isnt a cheap unit but it was cheaper than my fist choice. I do however buy all spectrapure replacement carts and media.
SPotter
Active member
no corals in that huge beautiful tank???????
Dmorty217
Saltwater Addict
I know most RO systems are the same in terms of function but the pricing is all over the place and some come with more specialized membranes that can only be bought from a few places.
No SPS... I don't have the OCD or patience for SPS. There will be some softies and LPS but probably nothing special if you will. I figure that the corals will get picked at by tank inhabitants so nothing difficult to keep or expensive to buy. Plus I'm not spending 2k on LEDs to put over this beast. Also with it being acrylic I don't want encourage coralline algae growth... After losing all my fish except 2 to secondary infections caused by prolong exposure to CP, I'm not exactly sure what direction I want to go in. Losing a couple of grand in fish 2 months ago has made me reevaluate what I want to be in the tank. A bunch of reef type fish will take me roughly a yr to stock in the tank after it's up and running due to limited QT space and the fact that QTing takes 3 months per group of fish/inverts. Decisions... Decisions...
FuzzyZipperbaum
New member
Why do you want 300 gpd? I have a system that is 2 500G tanks with two huge sumps...1 is a reef, 1 is a FOWLR (but monti grows great also)... I have 2 200G storage tanks... my 200 GPD is plenty... I always have 400g ready to go and can produce 200 in one day if needed....
sfsuphysics
Active member
Don't have a 300gpd unit, but I piggy back the waste water from one membrane through to another membrane, get less waste water overall and more production, probably not quite double the production of one membrane but maybe close (never been bothered to check). Do need higher than 40psi to make it work though.
That said, I'll say what I've been saying for years, there is really no difference between RO/Di systems other than bells and whistles they put on there.
The important choices
1) 10" or 20" pre-filters, 20" will last longer, not sure how they scale in price though
2) Rating of membrane, it's been a while since I looked around but 75GPD and less membranes have a 96% rejection ratings, where as 100GPD and above are 90%, this saves you money on DI replacement down the line.
3) Well bells and whistles do you want?
Now the kicker? You can change any system into any other system after the fact. Want 20" filters? buy a 20" slip housing. Want clear containers instead of solid? buy them (not sure if they have 20" clear). You want a inline TDS? buy it it's an option, want pressure gauge? another option. Larger membrane capacity buy them, more DI resin, add on another container. dual membranes? Add them.
Basically my recommendation is find out exactly what you want, find what system gives you that, then find out how much a cheap one would cost with all the additional parts added. Some of these filter people really love to gouge the aquarist by saying how good their system is compared to another. Of course I say this because I already have an RO/DI system, it was a 25GPD system (RO only when I bought it) and I've turned it into a 150GPD system with TDS, pressure and 3 chambers of DI resin.
That said, I'll say what I've been saying for years, there is really no difference between RO/Di systems other than bells and whistles they put on there.
The important choices
1) 10" or 20" pre-filters, 20" will last longer, not sure how they scale in price though
2) Rating of membrane, it's been a while since I looked around but 75GPD and less membranes have a 96% rejection ratings, where as 100GPD and above are 90%, this saves you money on DI replacement down the line.
3) Well bells and whistles do you want?
Now the kicker? You can change any system into any other system after the fact. Want 20" filters? buy a 20" slip housing. Want clear containers instead of solid? buy them (not sure if they have 20" clear). You want a inline TDS? buy it it's an option, want pressure gauge? another option. Larger membrane capacity buy them, more DI resin, add on another container. dual membranes? Add them.
Basically my recommendation is find out exactly what you want, find what system gives you that, then find out how much a cheap one would cost with all the additional parts added. Some of these filter people really love to gouge the aquarist by saying how good their system is compared to another. Of course I say this because I already have an RO/DI system, it was a 25GPD system (RO only when I bought it) and I've turned it into a 150GPD system with TDS, pressure and 3 chambers of DI resin.
