yes that could work but just a word of caution eventually all pumps wear out and some wear out at different rates so with that being said there might come a time were those two pumps will have different flow rates which will either A. take more water out the tank than they are putting in or B. put more new saltwater in the tank than the other pump is putting in
is there an easy way to do water changes?
- Thread starter FortuneFavours
- Start date
shermanator
New member
If you can calibrate the pumps individually and update the calibration monthly (or quarterly at least), it would work. This is the idea behind most AWC systems. Keep in mind that even identical pumps will deliver different amounts, so a means to calibrate is essential. With any AWC setup, I'd also be monitoring salinity often (ideal would be controller with salinity probe).
Wryknow
New member
OK, here's the easy way to automate it IMHO.
1) Drill a drain hole in your sump that is just above the water line when your main pump is turned off and the sump is at maximum capacity. Plumb this directly to an external drain that is below the water line.
2) Have a SW mixing container with a pump connected to the controller.
3) Have the controller turn off the DT return pump(s). Wait a couple of minutes to allow the water level to stabilize and then have the SW mixing pump pump fresh SW in the DT. (Have this timed based on the pump flow and how much water you want to change.)
4) Excess water drains automatically out of the sump drain.
5) Turn on the return pump(s.) Water change is complete.
This is a simple and effective way to automate water changes provided that you keep the SW mixing container full. Trying to match pump speeds on a drain and input is just going to cause troubles long term IMPE.
1) Drill a drain hole in your sump that is just above the water line when your main pump is turned off and the sump is at maximum capacity. Plumb this directly to an external drain that is below the water line.
2) Have a SW mixing container with a pump connected to the controller.
3) Have the controller turn off the DT return pump(s). Wait a couple of minutes to allow the water level to stabilize and then have the SW mixing pump pump fresh SW in the DT. (Have this timed based on the pump flow and how much water you want to change.)
4) Excess water drains automatically out of the sump drain.
5) Turn on the return pump(s.) Water change is complete.
This is a simple and effective way to automate water changes provided that you keep the SW mixing container full. Trying to match pump speeds on a drain and input is just going to cause troubles long term IMPE.
karimwassef
Active member
I agree with the passive export via the overflow. You need a drain that's lower than the drain line level and to size the new SW flow to be slower than the max drain flow (hose size). Also need to add the new water far from the export location or you would be throwing clean water down the drain.
That's a disadvantage of a continuous vs. on/off changer.
That's a disadvantage of a continuous vs. on/off changer.
FortuneFavours
New member
I think that's a good reason to use dosing pumps for small daily changes, so there isn't a massive problem all at once. I think I'll probably end with water level alarms all over the place anyway...
I think calibration would have to be part of my monthly maintenance schedule. I'm going to have a salinity monitor, so will definitely be keeping an eye on the levels.
Whilst this is a good idea, I like the idea of smaller daily water changes so I think I'm going to use the dosing pumps. This has the added benefits of:
a) not having to drill any holes
b) not having to turn any equipment off when undertaking water changes
FortuneFavours
New member
By the way, here's is a good article that I came across a earlier today (well, I've only read the beginning and the end. Lol).
FortuneFavours
New member
With the dual dosing pump setup, the amount removed would be the same as the amount added (provided they're calibrated properly), so sizing drains/flows shouldn't even be an issue.
As the water changes would be small, a waste water container could even be used instead of hard plumbing to the household drains. Although this container would require emptying regularly. I'd probably hard-plumb to the household drains, so that I'd have one less thing to worry about.
Having the new water enter the system away from the waste water inlet should be pretty straight forward with a dosing pump too - just run the flexible hose that will deliver the new water along the euro-bracing I have and into the opposite corner. No plumbing to worry about.
Even if the dosing pumps aren't properly calibrated, the daily difference between waste water removed and new water added should be minimal, given the small amount of water changed daily. Obviously this could cumulatively affect the salinity levels, so it would be important to keep an eye on the levels as suggested previously.
I'm pretty sold on the dosing pump idea now!
FortuneFavours
New member
After doing some digging, I've found that there are other people who have tried this approach!
Spaced Cowboy
South Bay Reefer
Here's how I intend to do it when I set up my new system in 6 months or so.
One of the big issues with timed systems (i.e. pump out for 6 mins, pump in for 6 mins) is that pumps are very rarely in sync with each other, and in fact they vary over time as motors wear in, the pump collects detritus or particulate matter etc.
So, don't use time. Use volume.
There exist digital flow meters that are simple to hook up to an arduino or arm board and count the volume (independent of time) that has flowed through a pipe. The above even comes with an LCD meter to get you started.
Get two of them. Procedure is:
If you don't have enough space in your sump to meter the water out/in you'll have to meter out from your display tank instead, and (assuming your water change is more than your overflows will allow the tank to drain) the procedure becomes
The nice thing about all this is that once you have some confidence in the system, it's easy to link it up to a reef-controller and completely automate it since the reef controllers have digital inputs (place an arduino between the meter and the controller, and have it count pulses then set a pin high/low to indicate completion. Link that pin to the controller) and can control the pump power.
The only thing to remember if you're going to automate it is that most pumps will not prevent a siphon from being formed once the flow has started and they are subsequently switched off. The easiest way to deal with this is to have the pumps pump upwards and deliver the water via an air-gap above the water-line of the source. Then no siphon can ever be formed.
Simon.
One of the big issues with timed systems (i.e. pump out for 6 mins, pump in for 6 mins) is that pumps are very rarely in sync with each other, and in fact they vary over time as motors wear in, the pump collects detritus or particulate matter etc.
So, don't use time. Use volume.
There exist digital flow meters that are simple to hook up to an arduino or arm board and count the volume (independent of time) that has flowed through a pipe. The above even comes with an LCD meter to get you started.
Get two of them. Procedure is:
- Turn off the return pump
- Meter out N gallons of sump water to the drain
- Meter in the same N gallons of NSW from the mixing tank to the sump
- Turn on the return pump
If you don't have enough space in your sump to meter the water out/in you'll have to meter out from your display tank instead, and (assuming your water change is more than your overflows will allow the tank to drain) the procedure becomes
- Turn off the return pump
- Meter out N gallons of display tank water to the drain
- Turn on the return pump
- Meter in the same N gallons of water to your sump
The nice thing about all this is that once you have some confidence in the system, it's easy to link it up to a reef-controller and completely automate it since the reef controllers have digital inputs (place an arduino between the meter and the controller, and have it count pulses then set a pin high/low to indicate completion. Link that pin to the controller) and can control the pump power.
The only thing to remember if you're going to automate it is that most pumps will not prevent a siphon from being formed once the flow has started and they are subsequently switched off. The easiest way to deal with this is to have the pumps pump upwards and deliver the water via an air-gap above the water-line of the source. Then no siphon can ever be formed.
Simon.
karimwassef
Active member
Two active systems trying to match each other is a lot harder and more painful than drilling one small hole in the sump. If you dose small volume, then the other issues go away.
Passive is a significantly more robust, simple and elegant solution - especially for the lazy minimalist effort and maintenance user.
Passive is a significantly more robust, simple and elegant solution - especially for the lazy minimalist effort and maintenance user.
sfsuphysics
Active member
How automatic do you want it to be? Like a controller doing everything on it's own? I would never recommend that for anyone, if someone is going to do it... so be it I won't try to talk them out of it, but never would I recommend it.
Now if you want to make your water change easier, few things you can do, you can have a hole drilled in the back/side whatever connected to a ball valve, turn off your return pump, open the valve, you'll drain precisely the same amount of water each time (but you need to make sure to turn off the return pump!)
You could also attach a piece of PVC to return line when you're get ready to do a water change, have tee off your return with two valves, close one, open the other, turn off pump and drain the tee to wherever the water is going. This will have some timing issues, but again you'll siphon drain the same amount.
You could just build a PVC "U" shape that fits perfectly over the edge of the tank, turn off return, manually suck a siphon, drain until the siphon breaks on it's own.
All ways of making sure you get a similar amount of water out of the tank.
Of course I like to use water change time to siphon detritus off the bottom, so for me doing something like this wouldn't be too useful. I do have a level though that I drain to so I know when to stop.
Now if you want to make your water change easier, few things you can do, you can have a hole drilled in the back/side whatever connected to a ball valve, turn off your return pump, open the valve, you'll drain precisely the same amount of water each time (but you need to make sure to turn off the return pump!)
You could also attach a piece of PVC to return line when you're get ready to do a water change, have tee off your return with two valves, close one, open the other, turn off pump and drain the tee to wherever the water is going. This will have some timing issues, but again you'll siphon drain the same amount.
You could just build a PVC "U" shape that fits perfectly over the edge of the tank, turn off return, manually suck a siphon, drain until the siphon breaks on it's own.
All ways of making sure you get a similar amount of water out of the tank.
Of course I like to use water change time to siphon detritus off the bottom, so for me doing something like this wouldn't be too useful. I do have a level though that I drain to so I know when to stop.
jonmprofeta
New member
My tank is built in my wall in my basement. All I have to do is turn off my ato. Turn on my pump that pumps out 10g at a time and turn another pump on to add the new saltwater. That's how I used to do it till I got my reef keeper. Now it dose it all by itself. I just have to mix up the saltwater.
Last edited by a moderator:
karimwassef
Active member
I use a "hose/fine net" assembly to the sump to vaccum detritus. With a 660g, I really like the convenience of a lazy water change process.
I get the best of both.
I get the best of both.
RoDogVillan
New member
U guys make that shot way to hard. Got a 75 gallon. I drain the water with the syphon into my ro comtainers. Dump it out fill the ro containers with the new saltwater and syphon it back in
jonjonwells
Member
Here is my thoughts on design using a controller and floats.
Storage tank for top off
Storage tank for fresh saltwater
1. Normal operation
2. Turn on ATO till full - float
3. Turn off ATO
4. Turn on water change pump - draining water for 30 seconds.... or however long
5. Turn on fresh salt pump till top off float is hit
6. Resume normal operation
This is the basic design that I am starting. I will also add a safety float in my salt water storage tank. If the level gets too low, the controller will not cycle the water change.
The one thing about this design compared to others is that by using floats, it does not matter if the separate pumps are different rates.
I also can easily adjust the amount of water to be changed by running the drain pump for different times.
Storage tank for top off
Storage tank for fresh saltwater
1. Normal operation
2. Turn on ATO till full - float
3. Turn off ATO
4. Turn on water change pump - draining water for 30 seconds.... or however long
5. Turn on fresh salt pump till top off float is hit
6. Resume normal operation
This is the basic design that I am starting. I will also add a safety float in my salt water storage tank. If the level gets too low, the controller will not cycle the water change.
The one thing about this design compared to others is that by using floats, it does not matter if the separate pumps are different rates.
I also can easily adjust the amount of water to be changed by running the drain pump for different times.
Sacohen
New member
Myself and a bunch of others have been using a double headed peristaltic pump to remove and replace water at the same time and since it is 1 motor turning pump heads at the same time the speed and everything are very consistent.
Here is the thread....
http://www.reefcentral.com/forums/showthread.php?t=2349824
Here is the thread....
http://www.reefcentral.com/forums/showthread.php?t=2349824
Duc1098
New member
I'm building a new tank and going to try something different that i came across a while back. Before I only had a 3- compartment refugium for filteration and I would turn off the pumps and siphon out all the water and crap in the skimmer chamber. It was a pain and a mess to do this. This new plan I saw someone else on RC do was use two 40g breeders that ran in series, if you look at it like a circuit. Basically, the drain from the tank was directed to one of the 40g breeders and collected all the detrius and then flow to his refugium in another sump. While this was going on the other 40g breeder was offline and had fresh SW mixing. When its time to do a water change you take the first tank offline and place the fresh one online. From there you can drain the offline tank and clear out all the debris and get it ready to start a fresh batch of SW. Only downside is that you will need plant of room for the extra tanks, not something you could do under a stand.
dcforester1
Member
I think SpectraPure figured it out for you and its called the Liter Meter III. I have been using one for a constant WC for about three years with no issues. I just have to remember to fill my 55gal drums every three weeks
