Diablo

Looking for help in building water change Station

Jonathan Chia

Supporting Member
Hi all,

We're getting a shed build in the backyard and my hope was to put a water changing station in the shed.

I have 2 32G Brute Trash cans with lids and a RODI unit, but I'm not really sure how to best setup / plump it so that I can have my RODI auto fill the Brute Trash can and have it drain to the next bin to make fresh salt and have fresh RO on hand.

The bins would likely be side by side instead on top of each other as I'm not sure I'd have the vertical clearance. Any help/guides would be appreciated
 

sfsuphysics

Supporting Member
There are a number of auto-water fill devices out there which I would highly recommend, Tunze makes one I believe, Avast makes 2 of which I have the one that uses the Apex as an interface... unfortunately don't have an Apex *DOH!*. But these devices are great because they have a low level detection and a high level detection and will allow your RO unit to turn on if it gets to a certain low point in your RO reservoir then stops when it gets to a high point so you don't have to worry about having RO/DI water on hand.

If you are really insistent on side by side, then you need to have a pump that's plumbed into the bottom of the RO container and fills into the SW container from the top but make sure the pipe never can go below the water line you do not want to siphon saltwater back into your RO container and contaminate that water. The SW container can be plumed fairly easily, you can be fancy and cycle water with an external pump pulling from the bottom pushing into the top, you can just toss a powerhead into the bucket and let it circulate constantly, or you can use a single external pump with both containers and through a series of ball valves and tees you can isolate where the water comes from so that there is at most a minimal level of contamination with your RO reservoir.

How are you planning on using this water? Are you going to plumb directly to where your tanks are? Are you just going to fill up in the shed and take to the tank with smaller buckets? Are you going to pull a long hose from the shed to the tank every time you need water?
 

Jonathan Chia

Supporting Member
I was just going to have the water on hand in the shed, and then fill up 5G buckets to add fresh salt / RO water. I like the idea of having the external pump pulling from the bottom and then pushing into the top
 

sfsuphysics

Supporting Member
Well if you're going to fill buckets you will need to either a) elevate the containers with a valve at the bottom so you can fill them up. If you use an external pump you can always put a tee (or multiple tees if you go nuts with the plumbing) with a valve so so you can just fill your bucket up that way if you want.
 

Jonathan Chia

Supporting Member
What would I need in terms of plumbing parts? I see some people have bulkheads, some just use uniseals? Can I just use uniseals and PVC pipes?
 

ashburn2k

Webmaster
Staff member
i would probley say all depends how you want to do it, i'd look for pump first, and work my way with the external pump's required connection.
 

sfsuphysics

Supporting Member
Uniseals are a prefered method when dealing with curved surfaces like trash cans, the down side is you do need to make the hole the exact size, bulkheads allow for a little play but you have to force the surface into a flat shape.

PVC size should line up with your uniseal hole size but you can always have different sizes if you use reducers or what not.

That pump might be a little much for an external pump, and definitely need to change your pipe size at least with reducers to fit the threads. Those pumps are not known for being very energy friendly
 

Vhuang168

Supporting Member
Make sure to drill the holes for the uniseals using the size recommended by the manufacturer.


Sent from my iPhone using Tapatalk Pro
 

rygh

Webmaster
So back up a bit...
You do not actually need to transfer water from RODI barrel to SALT barrel.

The trick : Put a TEE on the output of your RODI water maker, to both barrels.
Both barrels also need a float valve (not switch) to automatically stop RODI maker.
But also put an extra manual valve on the line to the SALT barrel.

So when you want to make new salt water:
Turn on that special valve a day ahead. It will fill and stop automatically much like normal RODI.
Then turn valve off, and mix up a big batch of salt water.

The RODI barrel acts as normal.

FYI : Suggest powerheads for mixing salt, not pumps.
Far less power, trivial to clean, no plumbing.
 

xcaret

Guest
I have two 50g water barrels that are looking for a home and if you want to try a "continuous water change" system, I also have a Masterflex dual head pump.
I think if you are going to have a shed for water mix/change, go as big as possible with the container; not the size of a swimming pool.
 

rygh

Webmaster
50G water barrels (or the X-large Brute) really help if you use IO salt.
You can mix a full bag at once, no measuring!
 

jccaclimber

Supporting Member
Mario, I'm curious, what was the noise level on the Masterflex compared to other dosing pumps?

As for mixing, I personally like to T the RO in to both containers, but 95% of the time I leave the T to the salt container shut. This way I have a big container of fresh ready, but my salt container doesn't change salinity until I choose to refill it from the fresh container. If I ever need to fill both at the same time I have the option still. This is only useful if you don't mind keeping pre-mixed salt water on hand, which of course has upside and downsides.
Last time I set up a mixing station for someone I made it so that the volume of the salt container (at a mark, and minus the dead volume) was just the right amount of water to dump in 1 bag of salt mix and end up at 1.025. This works pretty well if you always buy a specific brand and bag size of salt. If I'd been thinking I also would have put 1.024 and 1.026 marks in the container for correcting salinity during a water change.
Also, put a transfer pump somewhere in the system. If you plumb one pump in to both tanks with shutoff valves you'll get slight cross contamination, but this really doesn't matter in most circumstances. Note, if you run a kalk system you will get some precipitation from this in your kalk container, so flush the line first if you do both.
The other benefit of the transfer pump, aside from filling jugs faster, is that you can put the outlet back in to the salt container. This way you can fill it with fresh, dump in your salt, then just come back in an hour when its all mixed up.
 

sfsuphysics

Supporting Member
So back up a bit...
You do not actually need to transfer water from RODI barrel to SALT barrel.

The trick : Put a TEE on the output of your RODI water maker, to both barrels.
Both barrels also need a float valve (not switch) to automatically stop RODI maker.
But also put an extra manual valve on the line to the SALT barrel.

So when you want to make new salt water:
Turn on that special valve a day ahead. It will fill and stop automatically much like normal RODI.
Then turn valve off, and mix up a big batch of salt water.

The RODI barrel acts as normal.
This really only works if you use 100% of the salt water, and even then there might be some residual SW in the bottom of the container that doesn't come out so there would be a tiny amount of contamination. Now is it big? Probably not, but over any long enough time span even water at 1.001 will eventually start causing a salinity creep just from "FO" top off.

Now I don't know, maybe I'm weird in that I don't use all my SW at once, if I get low I say "hey time to refill"
 

jccaclimber

Supporting Member
This really only works if you use 100% of the salt water, and even then there might be some residual SW in the bottom of the container that doesn't come out so there would be a tiny amount of contamination. Now is it big? Probably not, but over any long enough time span even water at 1.001 will eventually start causing a salinity creep just from "FO" top off.

Now I don't know, maybe I'm weird in that I don't use all my SW at once, if I get low I say "hey time to refill"
1) I’m not following how this results in contamination of the fresh water.
2) I’m also not clear how this results in long term salinity drift. Small sources in salinity error, while avoidable, should be corrected with water changes or other more direct corrections by a remotely diligent aquarist.
 
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