Auto water change

Allan T

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I was wondering if doing weekly or bi-weekly water changes would affect SPS Coral as the parameters I'm sure change a little bit each time. I know consistency or gradual changes is the key. Would it makes sense to have a system that changed say a gallon of water three times a day and if so how can that be set up if you've done it?
 

Reef Jedi

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3 times a day may be overkill.

What controller are you using to automate this task? Apex or hydros? Knowing that will help me answer better.
 

Pistondog

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I was wondering if doing weekly or bi-weekly water changes would affect SPS Coral as the parameters I'm sure change a little bit each time. I know consistency or gradual changes is the key. Would it makes sense to have a system that changed say a gallon of water three times a day and if so how can that be set up if you've done it?
Many of us do this for the reason you stated, consistency. We change a gallon, about 1%, daily, using 2 versa pumps, 1 in and 1 out. The pumps come on for 20 minutes every other hour.

Hey, welcome to r2r.
 

edsbeaker

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I do auto water changes just as a convenience using a Neptune DOS controlled by my Apex. I think it probably does keep the tank more stable than weekly water changes, but I don’t think doing it manually once a week does any harm. People have been running successful reef tanks for decades without auto water changes. So, for me it is just to reduce my tank work. Additional stability is just a happy bi product of that.
 
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Allan T

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3 times a day may be overkill.

What controller are you using to automate this task? Apex or hydros? Knowing that will help me answer better.
I don't have a water changing controller yet but was looking at them and making a decision as to whether I needed one based on that. Was looking at the Apex.
 

BriDroid

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I’m a huge fan of auto water changes. My nano is controlled with Hydros. I use cheap peristaltic pumps and do a 700ml water change daily in the morning before the lights come on and anything is dosed. Since I’ve started the AWC, my growth and tank stability has been awesome. I’m a huge believer in them!
 

TheNative192

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I’m a huge fan of auto water changes. My nano is controlled with Hydros. I use cheap peristaltic pumps and do a 700ml water change daily in the morning before the lights come on and anything is dosed. Since I’ve started the AWC, my growth and tank stability has been awesome. I’m a huge believer in them!

I am curious what gear you have to run the Auto water change. I have a hydros doser, ato pump & sensor laying around. I am happy to get another doser as well if its safer than using the ATO pump. I am not sure how I could fit that in too tbh. I also have a Hydros Control X4 & XP8. I have a separate ATO for RODI with a Tunze Nano but how do you do dosing with All for Reef & have an autowater change. Also do you worry about the calibration being off changing the salinity in the tank? If you have two peristaltic pumps couldn't it possible remove more water than it adds or add more water than it should? If you have how you did it posted I would definitely be interested in checking it out!
 

BriDroid

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I am curious what gear you have to run the Auto water change. I have a hydros doser, ato pump & sensor laying around. I am happy to get another doser as well if its safer than using the ATO pump. I am not sure how I could fit that in too tbh. I also have a Hydros Control X4 & XP8. I have a separate ATO for RODI with a Tunze Nano but how do you do dosing with All for Reef & have an autowater change. Also do you worry about the calibration being off changing the salinity in the tank? If you have two peristaltic pumps couldn't it possible remove more water than it adds or add more water than it should? If you have how you did it posted I would definitely be interested in checking it out!
When I mix up my Pro-Reef, I add 0.11g of baking soda. That puts the dKH right at or slightly above 8. I do my 600ml AWC at 7:40am everyday. I start dosing 9.8ml of AFR at 9:00am and do 7 small doses until 3:00pm. My alkalinity stays in the 8dKH.

I use a triple sensor for my ATO, which is also the high level for the AWC. I have a low level sensor that the drain runs until it goes dry, then the fill runs until the high level sensor goes wet. That way I don’t need to worry about any calibration of the pumps. It takes about 8-9 minutes to drain and fill 600ml, so I have a 10 minute max run time just in case one of the sensors gets dirty, which has happened once.
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TheNative192

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When I mix up my Pro-Reef, I add 0.11g of baking soda. That puts the dKH right at or slightly above 8. I do my 600ml AWC at 7:40am everyday. I start dosing 9.8ml of AFR at 9:00am and do 7 small doses until 3:00pm. My alkalinity stays in the 8dKH.

I use a triple sensor for my ATO, which is also the high level for the AWC. I have a low level sensor that the drain runs until it goes dry, then the fill runs until the high level sensor goes wet. That way I don’t need to worry about any calibration of the pumps. It takes about 8-9 minutes to drain and fill 600ml, so I have a 10 minute max run time just in case one of the sensors gets dirty, which has happened once.
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You are a beast! Do you use dosing containers for the AWC or just buckets to contain the water. I have never used a doser so I am not exactly sure how they work yet. Need to do some testing. I like the way how you do it with the sensors as well. Curious what doser pumps you currently use for the AWC as well if you don't mind me asking!
 

BriDroid

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I use these jugs from BRS. They actually hold 1.25 gallons, so that give me 7 days of water. I drain into one and fill from the other.
IMG_0746.png
These are the peristaltic pumps I use. I got them from AliExpress for cheap. You can buy the rebuild kits from Amazon to keep them running. Really simple, but reliable little pumps.
IMG_0747.jpeg

I also use two of the skimmer overflow sensors, one in each jug to let me know when the drain is full or the supply is dry, just in case I forget to change them. They read just fine through those jugs.
 

TheNative192

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I use these jugs from BRS. They actually hold 1.25 gallons, so that give me 7 days of water. I drain into one and fill from the other.
IMG_0746.png
These are the peristaltic pumps I use. I got them from AliExpress for cheap. You can buy the rebuild kits from Amazon to keep them running. Really simple, but reliable little pumps.
IMG_0747.jpeg

I also use two of the skimmer overflow sensors, one in each jug to let me know when the drain is full or the supply is dry, just in case I forget to change them. They read just fine through those jugs.

So I actually ended up ordering the space-saver jugs as well. I also picked up a 1/4″ push-connect bulkhead tank adapter and a 16″ length of 1/4″ clear acrylic tubing so I can connect the source water. The funny part is I don’t own a drill, so I’ll need to borrow one or grab one before I can install the bulkhead.

I also ordered the triple HYDROS sensor and plan to use the ATO sensor as the low-level point. When I spoke with someone from HYDROS, they recommended not running the dosing pumps for more than about five minutes at a time, so it’s better to do multiple smaller water changes throughout the day rather than one large change.

I picked up a skimmer sensor as well. I think I’ll only have one sensor slot available as I will have one for temperature, one for the triple water level sensor, one for the low water level sensor, & the final slot for the skimmer sensor in the container; So my plan is to place it in the saltwater fill reservoir. That way, an auto water change won’t initiate unless there’s enough water in the tank—at least that’s the logic I’m going with.

I also ordered a second HYDROS dosing pump so I can dedicate one to All-For-Reef dosing (if I have the space for it on my board (will not need to dose anytime soon though with current corals), and I’ll likely use the HYDROS ATO pump to refill the tank with saltwater until it hits the sensor after each change. And, of course, I grabbed a proper probe and tubing holder too, since the one I’m using now definitely needed an upgrade.
 

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