Lets talk Auto water changes... AWC 101

[Devaji]

SO if all goes as planned I will be setting up an AWC. mixing station/top off will be in basement.
I have some questions for you guys?

~I have the full apex so it makes since to go with a DOS correct? any other system I should be looking into? i know auto aqua makes one as well as another but looks like apex is what most ppl use?

~ what % of tank volume are you guys changing per day? ie. 1 gal per day on a 100 gal tank..

~ATO must be off when scheduling AWC correct?

~ "best" mixing containers? I like the 50-65 gal white ploy containers but brute trash cans sure are cheaper. anything else one should look into?

~ what in the max head height on the Pmup for the ATK will in push about 8 feet of head height in to sump from basement?

~ is the solenoid valve a must back up to stop siphon in case DOS head goes out? any other options?

~ how long is your DOS heads lasting doing AWC?

~ soft tubing VS hard RO tubing?

~ how long is the DOS cable to apex? I head there loud when working to do AWC so I hope to have that in the basement but my apex up in the stand.

~ do you heat you mixed salt? ( guessing you dont when doing a low volume per day)

~ how often must you mix the salt? x times per day for Y long plz

~ thinking it's a good idea to elevate your mixing stations so you can drain them if need be true?

any other tops tricks and must knows very mush welcome!
cheers,
D

 

[Devaji]

anyone?

 

[DelRayTank]

I’m also planning an AWC system, looking at the DOS. Signing up to follow this thread.

 

[lbacha]

I use 2 BRS 50ml/min dosing pumps to do a 1/2 gal water change twice a day. I have both run at the same time so no need to worry about turning your ato off. While I’m sure they aren’t perfectly calibrated the extremely small change in salinity that probably occurs isn’t enough for me to worry about and I check salinity weekly and make adjustments by pulling water out and letting the ato add RODI back or adding more fresh saltwater and letting the tank evaporate it off to raise the salinity.

The third doser is for topping my ATO container that is next to my tank off

 

[BZOFIQ]

https://www.reef2reef.com/threads/let’s-mix-it-up-designing-and-using-a-water-mixing-station.270585/

https://www.reef2reef.com/threads/automatic-water-change-1.545636/

All you need to know.

 

[Devaji]

I use 2 BRS 50ml/min dosing pumps to do a 1/2 gal water change twice a day. I have both run at the same time so no need to worry about turning your ato off. While I’m sure they aren’t perfectly calibrated the extremely small change in salinity that probably occurs isn’t enough for me to worry about and I check salinity weekly and make adjustments by pulling water out and letting the ato add RODI back or adding more fresh saltwater and letting the tank evaporate it off to raise the salinity.

The third doser is for topping my ATO container that is next to my tank off

oh nice I did not think about using the BRS dosing pumps. great idea. i'll price it out but i do like the connectivity of the DOS tho...

 

[Devaji]

https://www.reef2reef.com/threads/let’s-mix-it-up-designing-and-using-a-water-mixing-station.270585/

https://www.reef2reef.com/threads/automatic-water-change-1.545636/

All you need to know.

I did read the the lets mix it up late last night instead of sleeping..haha
thanks for the info i'll look at it again as well as the other one.

 

[SuncrestReef]

I use the DOS and run continuous water changes (24 hours per day) of 2 gallons per day on my Reefer XL 425 (112 gallons total system), so that's approximately 12% weekly.

Since it adds and removes water at the exact same time, the level remains constant so you don’t need to turn off the ATO. The amount of new water loss due to blending is minimal as long as your drain tube is upstream from your add tube.

To answer more of your questions:

~ what in the max head height on the Pmup for the ATK will in push about 8 feet of head height in to sump from basement?
14 feet

~ is the solenoid valve a must back up to stop siphon in case DOS head goes out? any other options?
The DOS head pinches the tubing in multiple places, so it's very unlikely to happen unless the head pops off (next to impossible) or it has some sort of catastrophic failure. It would be extremely difficult to program for the solenoid since the DOS turns on and off frequently during the interval, and there's no programming variable that states when the DOS is actually running.

~ how long is your DOS heads lasting doing AWC?
I changed mine for the first time after 10 months of use. I didn't see any noticeable damage, so I'm guessing it would have lasted much longer.

~ soft tubing VS hard RO tubing?
I used 1/4" color-coded RO tubing -- orange for new water and black for waste water.

~ how long is the DOS cable to apex? I head there loud when working to do AWC so I hope to have that in the basement but my apex up in the stand.
The included cable is only about 10 or 15 feet long (can't remember which). I bought a 30 foot AquaBus cable here: https://www.usbfirewire.com/parts/rr-apex-xx.html
They're available up to 125 feet.

~ do you heat you mixed salt? ( guessing you dont when doing a low volume per day)
I do heat my salt, but primarily to give more accurate salinity readings. My RO/DI water comes out at about 55 degrees.

~ how often must you mix the salt? x times per day for Y long plz
I just leave a very small powerhead running 24/7 in the mixing tank. It has really helped prevent sediment buildup inside the storage tank.

~ thinking it's a good idea to elevate your mixing stations so you can drain them if need be true?
YES! And be sure to add ball valve spigots at the bottom with enough room to place a bucket below them. Many people overlook this design. I can't tell you how often I like to dispense some saltwater or RO/DI water into a bucket for simple things like dipping corals, rinsing equipment, etc.

any other tops tricks and must knows very mush welcome!
I added optical sensors so my Apex can alert me about low or high water levels in the storage tanks.

I wrote up details of my mixing station build with a full parts list in my build thread:
https://www.reef2reef.com/threads/s...efer-xl-425-build.358990/page-34#post-6173194

 

[Devaji]

@SuncrestReef very nice mixing AWC station! I hope to set up ( once we move) AWC on my RS 750XXL =200 gal total water volume.
is there a "rule of thumb" tank size to daily water change? i know each system is unique..

I am thinking 1 to 2 gallon a day and go from there.

this may be a stupid question but...
guessing ppl stop AWC for one day while mixing new salt? adding new RODI water will be quick and easy from the storage container but it still needs to mix.

and how do you do the math say you go to make new SW and your tank is 10% full. I am sure I am way over thinking this...

 

[SuncrestReef]

@SuncrestReef very nice mixing AWC station! I hope to set up ( once we move) AWC on my RS 750XXL =200 gal total water volume.
is there a "rule of thumb" tank size to daily water change? i know each system is unique..

I am thinking 1 to 2 gallon a day and go from there.

this may be a stupid question but...
guessing ppl stop AWC for one day while mixing new salt? adding new RODI water will be quick and easy from the storage container but it still needs to mix.

and how do you do the math say you go to make new SW and your tank is 10% full. I am sure I am way over thinking this...

(Note: I edited my original post above to answer more of your questions, so you may want to go back and read the new content)

The "rule of thumb" is all over the map. I like to change approx. 10% weekly.

Yes, I set up a virtual output to turn off or turn on the AWC with a single click so I can mix new water. Alternatively you can just turn off both DOS heads, but that requires two clicks.

My 75 gallon mixing tanks have gallon markers ever 5 gallons. When my tank is low, I just note where the water level is relative to the nearest 5 gallon marker, then add 40 gallons of RO/DI to the tank. I then add 20 cups of salt (1/2 cup per gallon) and it mixes up perfectly at 1.026.

 

[SuncrestReef]

~ is the solenoid valve a must back up to stop siphon in case DOS head goes out? any other options?
The DOS head pinches the tubing in multiple places, so it's very unlikely to happen unless the head pops off (next to impossible) or it has some sort of catastrophic failure. It would be extremely difficult to program for the solenoid since the DOS turns on and off frequently during the interval, and there's no programming variable that states when the DOS is actually running.

I wanted to follow up on my response about using a solenoid to prevent a siphon:

I think the best safeguard would be use a check valve on the RO tubing. Again, it's highly unlikely the DOS head will allow a siphon, but this would add an additional layer of protection without the challenging need for programming a solenoid with the DOS schedule.

 

[biecacka]

I use the DOS for 2 gallons a day on my 240 gallon tank. I wanted a litremeter but got a good real on the DOS. I don’t have any issues with it excepts it’s a little noisy but I have grown used to it. The water is changed out over a number of small doses a day so the ATO is not effected by it. Thus meaning you don’t have to turn it off. I run my waste water down my washing machine drain.

Corey

 

[Devaji]

@SuncrestReef thanks so much for taking the time to answer my questions. I am sure it will help other ppl searching this topic as well.

to heat or not to heat my SW mix? I am guessing my RODI will come out in the low 40s in the winter put will warm up to room temp in the holding tank then over to SW mixing vat. will leave room heat on 60 if I can.
so maybe I can get away with out heating SW?

nice to know there is a long aquabus cable.

what size of pump do you use in your 75 vat?

 

[biecacka]

No need to heat it in my opinion. Unless your water change is that large. But for 1 gallon a day on 100 gallon tank I don’t see the value in it

Corey

 

[Devaji]

No need to heat it in my opinion. Unless your water change is that large. But for 1 gallon a day on 100 gallon tank I don’t see the value in it

Corey

Corey my thoughts too. I would be doing a 1 to 2 gallon a day for a 200 total volume system.

 

[Devaji]

anyone have any good leads on water holding tanks? now that rural king and others dont ship for free its quite expensive. shipping at tankdepo was 85% of tank price :O

might have to use brute or pick barrels if I can find em...

 

[SuncrestReef]

anyone have any good leads on water holding tanks? now that rural king and others dont ship for free its quite expensive. shipping at tankdepo was 85% of tank price :O

might have to use brute or pick barrels if I can find em...

I found mine locally on Craigslist. It turns out there was a small company nearby that specializes exclusively in water containers of all shapes and sizes. Might be worth checking your local area on Craigslist. Search for "water storage tank", "water storage container", or "water storage barrel".

 

[SuncrestReef]

@SuncrestReef thanks so much for taking the time to answer my questions. I am sure it will help other ppl searching this topic as well.

to heat or not to heat my SW mix? I am guessing my RODI will come out in the low 40s in the winter put will warm up to room temp in the holding tank then over to SW mixing vat. will leave room heat on 60 if I can.
so maybe I can get away with out heating SW?

nice to know there is a long aquabus cable.

what size of pump do you use in your 75 vat?

My pump is a Pan World NH-150PS. https://www.bulkreefsupply.com/pan-world-150ps.html

 

[Tastee]

@SuncrestReef thanks so much for taking the time to answer my questions. I am sure it will help other ppl searching this topic as well.

Second that, good topic, great reply. I am planning my own AWC so this is very helpful.

 

[Devaji]

was thinking about building water holding tanks out of acrylic 20x20x 36 =60+ gallons but when i priced that out...yeah back to the drawing board.

I did find 65 gallon containers for $199 at tractor supply but several hours drive away.