AWC with Jebao DP4 & reefpi ATO

[KonradTO]

Hi everyone,
As the title introduce, I am planning to use the Jebao DP4 (should arrive in a couple of days) for automatic water changes.
Now, I am not in crazy need/necessity for AWC giving that I have a 30 gal tank with less than 25-26 g water.. and I change around 8% water every week..
BUT since the price for the 2,3 and 4 head doser is similar (less than 80 €) I decided to get the 4 heads doser and use them for Ca, alk, AWC in and AWC out.
Also I hope I will get more stability in the alk in this way.
My idea is to set up a macro within reefpi which:
1) Turn off ATO
2) Turn off heaters (I have them right by the water margin and don't want to run them dry)
3) Use head 3 from the DP4 to discard 1-2 liter of water from tank into a reservoir
4) Run head 4 from fresh saltwater into the tank until the ATO float switch is in position
5) Turn back on heaters
6) Turn back on ATO

This should run once every 24h.
Now: I need to find a way to turn the DB4 head 4 off when the ATO float switches to closed. I have mainly 2 ideas:
1) use a relay to cut the power supply directly to the head 4 for few minutes for safety
2) Turn off/on quickly the DB4 given that it will stop disposing the liquid once disconnected

Is there something obvious I am missing here?

 

[SPR1968]

I can’t help with the specific question but I can bump the thread to see if we can get you some attention

 

[KonradTO]

Thanks today I received the doser. I will make some experiment later and write here the updates.. I hope that the doser stop dosing if temporarily turned off. That would make the whole thing easier to set

 

[chadfish]

If you set AWCout to the same volume as AWCin, how can you go wrong? Then you set a manual direct-close float switch higher up at an emergency level that physically restricts the flow from AWCin in case something goes crazy

 

[KonradTO]

If you set AWCout to the same volume as AWCin, how can you go wrong? Then you set a manual direct-close float switch higher up at an emergency level that physically restricts the flow from AWCin in case something goes crazy

Wouldn't restricting the INflow or OUTflow damage the dosing pump? My fear is that if that one of the pumps fail I will have issues with salinity (when ATO turns on and there is a different water level from the beginning). The easiest way I suppose is to use the same float as the ato to decide when to stop pouring fresh saltwater in

 

[chadfish]

Wouldn't restricting the INflow or OUTflow damage the dosing pump? My fear is that if that one of the pumps fail I will have issues with salinity (when ATO turns on and there is a different water level from the beginning). The easiest way I suppose is to use the same float as the ato to decide when to stop pouring fresh saltwater in

Maybe. Or maybe it would just pressurize the line, or maybe just spin in place. But it’s just for an emergency like if the Jebao doser malfunctions and decides it doesn’t want to shut off. The risk is also limited by how big your fresh salt water reservoir is. Are you drawing from a 100 gallon tank, or 5 gallons? Im not suggesting that 4 gallons on your floor is acceptable in any way, but you get the point, that you can limit your risk that way too.

Good luck however you set it up

 

[KonradTO]

Maybe. Or maybe it would just pressurize the line, or maybe just spin in place. But it’s just for an emergency like if the Jebao doser malfunctions and decides it doesn’t want to shut off. The risk is also limited by how big your fresh salt water reservoir is. Are you drawing from a 100 gallon tank, or 5 gallons? Im not suggesting that 4 gallons on your floor is acceptable in any way, but you get the point, that you can limit your risk that way too.

Good luck however you set it up

The point is to have the same amount taken out and poured in, I simply use less water than remaining capacity for safety.

 

[smallcrpt]

Hi everyone,
As the title introduce, I am planning to use the Jebao DP4 (should arrive in a couple of days) for automatic water changes.
Now, I am not in crazy need/necessity for AWC giving that I have a 30 gal tank with less than 25-26 g water.. and I change around 8% water every week..
BUT since the price for the 2,3 and 4 head doser is similar (less than 80 €) I decided to get the 4 heads doser and use them for Ca, alk, AWC in and AWC out.
Also I hope I will get more stability in the alk in this way.
My idea is to set up a macro within reefpi which:
1) Turn off ATO
2) Turn off heaters (I have them right by the water margin and don't want to run them dry)
3) Use head 3 from the DP4 to discard 1-2 liter of water from tank into a reservoir
4) Run head 4 from fresh saltwater into the tank until the ATO float switch is in position
5) Turn back on heaters
6) Turn back on ATO

This should run once every 24h.
Now: I need to find a way to turn the DB4 head 4 off when the ATO float switches to closed. I have mainly 2 ideas:
1) use a relay to cut the power supply directly to the head 4 for few minutes for safety
2) Turn off/on quickly the DB4 given that it will stop disposing the liquid once disconnected

Is there something obvious I am missing here?

Have you gone any further with this? This is exactly what i want to do?
Is your mixing station on the same floor? I would be one floor down and about 8 feet over from where I would want to mix.

 

[BoneDoc]

I have a jebao 4 head doser myself and it’s very inaccurate. It dosed 40ml when I set for 50. So you need to calibrate it to a known dose and check from time to time that it’s still doing the correct thing. This is definitely not a set it and forget it with the cheaper options.

 

[KonradTO]

Have you gone any further with this? This is exactly what i want to do?
Is your mixing station on the same floor? I would be one floor down and about 8 feet over from where I would want to mix.

I forgot to update here, my bad! I don't have any mixing station, as my tank is only 30g it is easy to prepare the water every week.
I managed to run it in this way:

1 "normal" Ato (ATO 1) turns off
2 heaters turns off
3 Pump 1 takes X amount of water out of the tank and dump it into WC canister
4 When pump 1 finishes I turn on a second ATO (call it ATO 2) which uses the same sensor as the "usual" ato but when it reaches the "right" level it turns off the whole DP4
5 Pump 2 take X+10% water from new saltwater reservoir and dump it into DT
6 When water level reaches the ATO sensor the ATO 2 turns off the DP4
7 After few minutes ATO2 is turned off, heaters, DP4 and ATO 1 are turned back on

I turn back the DP4 right after the job is finished because I am not sure how long the battery can store the memory with the settings. It is a fortunate coincidence that when the DP4 is turned off and turned back on every dosing it was conducting is interrupted.
The whole system relies on the match between reef-pi and the internal clock of the DB4, which is known for being not really reliable. This means that every now and then you need to re-adjust either the clock or the timing of the reef-pi macros.
Also, the pump2 refills the tank with X+10% water because I noticed that if it delivers slightly less water than pump1 there is the risk that your ATO1 will fill the tank with RODI. In the long term this will slowly decrease your salinity. Better safe than sorry!

I will update maybe a detailed build thread with pictures, I still need to write my "main" build thread so it might take a while. Anyway if my explanation was not clear I am happy to help!

 

[KonradTO]

Overall I must say I am pretty satisfied. The DB4 is quite accurate for the price and very quiet. Not sure how long it will last with such an intense use.. it takes 15-20 minutes of continuous use for 1l of water (0.25g I guess)

 

[KonradTO]

I have a jebao 4 head doser myself and it’s very inaccurate. It dosed 40ml when I set for 50. So you need to calibrate it to a known dose and check from time to time that it’s still doing the correct thing. This is definitely not a set it and forget it with the cheaper options.

Did you check your peristaltic pumps have been assembled properly? I found this video online


and I found out all my heads were assembled like that... I did not compare accuracy recently but it seems that at least it runs smoothly.

 

[KonradTO]

Have you gone any further with this? This is exactly what i want to do?
Is your mixing station on the same floor? I would be one floor down and about 8 feet over from where I would want to mix.

Also consider that peristaltic pumps are not affected by the height/distance between reservoir and target tank as far as I know. So no problem at all with 3-6 meters from one floor to the other, just remember to calibrate it once the tubing is set up and not before

 

[kagisexton]

I have a jebao 4 head doser myself and it’s very inaccurate. It dosed 40ml when I set for 50. So you need to calibrate it to a known dose and check from time to time that it’s still doing the correct thing. This is definitely not a set it and forget it with the cheaper options.

This is 100% correct. I now use it just for alk and ca which don’t have to be so accurate. With small doses (like 1ml a day for trace colors) it constantly loses prime. People pay more for dosers for a reason…. you get what you pay for.

edit: that being said, for awc, I’m sure it will work fine as that is not precision dosing.

 

[KonradTO]

This is 100% correct. I now use it just for alk and ca which don’t have to be so accurate. With small doses (like 1ml a day for trace colors) it constantly loses prime. People pay more for dosers for a reason…. you get what you pay for.

edit: that being said, for awc, I’m sure it will work fine as that is not precision dosing.

As everything when is about scale-dependant accuracy the solution is to dilute when possible.. if you dilute 10 times then you can dose 10 ml instead of 1ml, you just need to refill the reservoir more often. Sometimes spending more is not possible since its not only about dosers, but skimmers, led fixtures, tests, expensive frags etc.
Also many times when you spend less you can hack and make it better than 5 times more expensive devices, if you know how to do it