Auto Water Change Station

[smcnally]

Ok, so here's my plan. I HATE doing water changes, so I'm going to build and automatic changed station. Tell me what you think, and what you suggest I build it out of. I haven't decided if I want to use acrylic or marine grade plywood since it will only have water in it for about 12hrs a week. It will do a 10 gallon water change weekly. The only thing I should have to do manually is add the salt.

Materials:
2 float switches
2 relay actuated valves (1 to change closed loop to drain & 1 for second drain)
2 Mag 3 pumps 1 for closed loop & 1 for filling the "Old Water" side
1 heater

I plan to use my Crestron automation system to control it and it should work like this...

Once I press the water change button it will close both valves and start filling the "Mix Side" with water and turn on the heater. While it is doing this, I will add the salt.

After about 30 minutes it will start the Mag 3 up and start mixing the water. Once full, it will continue mixing for 12 hours.

When the mixing is done it will turn off the heater & my display tank return pump and start draining water from the display into the "Old Water" side of the unit.

Once the "Old Water" side is full, it will stop pumping from the main tank, actuate both drain relays, drain the newly mixed water into the display (via the sump), turning the display pump back on as well, and drain the old water outside.

I Figured the unit needs to be about 16"Wx16"Dx24"T (24 gal) which will give me some room for the switches to mount and such.


Anything I'm missing? What do you guys suggest?

 

[mloebl]

Neat idea Steve. I've thought about doing something similiar with my Homeseer home auto system. You may be able to save time/costs by picking up some old barrels. They have both 30g and 55g sizes, and with a side mount float switch should be able to keep both level.

My idea was a bit simpler than this based on my setup in the basement. I was thinking of adding a 2nd float switch in my sump at the same level as the autotop off is now. Then use a known marked level in the tank as the water level change level. Then have an old 55g drum premarked and measured with a float switch for incoming fresh so all I'd need is to add salt. The drain line on the tank is a T, one side going to sump, the other to the sewer line. It drains a LOT of water very fast, so my thought was to open up the sewer line side and drain to the known marked water change level (could in theory add another switch with a light to tell you, but why overcomplicate.) Then turn on the new water side and let it fill up until it hits the float switch and shuts off.

-Mike

 

[smcnally]

When do you plan on setting yours up? I was wondering today if it might just be easier to get a 25 gallon tank, drill it, and put a seperator in it.

 

[Gina McReeferson]

When do you plan on setting yours up? I was wondering today if it might just be easier to get a 25 gallon tank, drill it, and put a seperator in it.

Sounds much easier to me...

 

[marco67]

Why not use 2 seperate tanks? then there would be no seperator to leak/posibility fail.

 

[mloebl]

When do you plan on setting yours up? I was wondering today if it might just be easier to get a 25 gallon tank, drill it, and put a seperator in it.

I agree with Marco, unless you are low on space?

I am still hashing out some of the details, but I think I have all the components I need. I'm just really finishing the basement sump project, so just haven't gotten to this piece yet. My other thing is I need to stop being lazy and actually do a real measurement on water levels in the 55g drum instead of estimating

I actually think I have an idea that may simplify my design a bit further; the contacts on my float switch I believe are normally open. Right now it's connected to a modified peristaltic pump for topoff/dosing. I'm thinking to make sure the sump water level is consistent when done (so auto top off doesn't have to be tweaked and another hole drilled into the sump for the switch HOPEFULLY at the same level), I just parellel another connection off that same auto top off float switch. Save on parts and be level

So really my only challenge left is to determine what level I drop my sump to. I don't mind having extra salt water mixed up as I have another tank that needs water changes anyways. Plus if I have it marked off already on the barrel, if I know I am starting off with a barrel with 10g of salt water, if I add 30g of fresh, it's just 30 more scoops of IO.

-Mike

 

[smcnally]

Why not use 2 seperate tanks? then there would be no seperator to leak/posibility fail.

Have you ever seen how small my condo is?
I'm pushing it with a 125 gal...Never mind the new thing.

 

[delta]

Have you ever seen how small my condo is?
I'm pushing it with a 125 gal...Never mind the new thing.

Plus he needs space to put his fire extinquisher

 

[smcnally]

Plus he needs space to put his fire extinquisher

LOL...are you talking about that 20lb CO2 tank? That is only used in emergencies now I have a nice 5lb aluminum one now.

 

[Scuba_Dave]

I don't suppose you could build it outside & insulate it?
I guess the condo assoc wouldn't like that

 

[smcnally]

I don't suppose you could build it outside & insulate it?
I guess the condo assoc wouldn't like that

LOL...I wish. I can't even do a satellite dish. I know I can fight the dish issue and win, but it just isn't worth my effort.