Water Changes or AWCs... is one better than the other?

[LegendaryCG]

I've been thinking about setting up AWC on my system. I typically change ~100g every 2 weeks on my 600g system. What equipment and schedule do you use?

So to mirror that I'd setup a 7G a day water change cycle over a 24 hour period which should be doable with an Apex DoS.

 

[MarineMalecki]

That's a serious tank! Any pics?

@Angelwolf21203 Here's the build thread: https://www.reef2reef.com/threads/marinemaleckis-300g-600g-total-display.351950/. I haven't been diligent with posting updates, but there are some recent pics I recently uploaded. I used to have a link to it in my profile, but it is no longer there

 

[MarineMalecki]

So to mirror that I'd setup a 7G a day water change cycle over a 24 hour period which should be doable with an Apex DoS.

Thanks @LegendaryCG that's good to know......do you disable the ATO as well? I've seen several setups where people disable their ATO, replace saltwater, and then re-enable their ATO. Given the slower speed of the DOS, I'm guessing it would work OK to just keep the ATO on the whole time

 

[Crustaceon]

With doing AWC do you run a bare bottom tank or a sand bed? The idea of AWC always sounded good but when I do my 5% I always use a turkey baster to clean my rocks and sift through my substrate.

I still run a sandbed and part of my maintenance routine is using a turkey baster to blast the sand once a week, which knocks the crud into the water column and clouds the tank up. Typically an hour later the tank is clear again and I have the pleasure of swapping out a really dirty filter sock for a clean one. Even with a barebottom tank, unless if has insane flow, you’ll still have to manually remove detritus.

 

[Spieg]

I'm probably the wrong person to ask since I only do water change twice a year (mainly just to clean the sand bed). AWC seems pretty wasteful in that a portion of the water you are taking out today was just put in yesterday.

 

[Angelwolf21203]

What about using a weekly schedule, as opposed to a daily schedule? Then leave the ATO on to replenish any evap.

 

[Kikoboy]

To keep the parameters more stable, I do daily water changes of less than 1 %. I used to change a little over 1% per day, but noticed the water was a little too clean. I’m still playing around with the percentage, trying to find the perfect balance.

 

[Chefwheredyougo]

What about using a weekly schedule, as opposed to a daily schedule? Then leave the ATO on to replenish any evap.

That sounds like a good idea, easily done with the apex controller to set specific days of the week to change some water for you

 

[LegendaryCG]

Thanks @LegendaryCG that's good to know......do you disable the ATO as well? I've seen several setups where people disable their ATO, replace saltwater, and then re-enable their ATO. Given the slower speed of the DOS, I'm guessing it would work OK to just keep the ATO on the whole time

I leave mine on. It’s removing at the same rate as it’s adding so it doesn’t trigger the ATO. However, I have had the tubing clog which does create issues.

 

[Jax15]

With doing AWC do you run a bare bottom tank or a sand bed? The idea of AWC always sounded good but when I do my 5% I always use a turkey baster to clean my rocks and sift through my substrate.

It’s a good point. I have sand, so it’s part of my monthly maintenance to vac the sand through a filter sock. It’s an extra chore, but I still find it much easier to add this than doing the full water changes+vac.

 

[Jax15]

I am seriously considering buying this one.

In fact I posted about it this am. How do you have your reservoirs set up? I need to figure out a way to do it vertically next to the tank, because under the stand and through the wall are not an option.

I used that device on my previous 20g tanks. I mostly used it when I left on vacations, since I never 100% trusted it for daily work. It does work though, and is quite nifty. It also works great as a regular ATO, which is how I’m using it now.

Current AWC is done with the Do’s, and works great. You can look at the vertical RV water tanks, loke the one I use for my top off. Works great!

 

[Jax15]

I'm probably the wrong person to ask since I only do water change twice a year (mainly just to clean the sand bed). AWC seems pretty wasteful in that a portion of the water you are taking out today was just put in yesterday.

This is def true, and part of the reason why 2% changed daily doesn’t actually equal 14% weekly, for example (Prob more like 10% net). It does add stability overall though.

 

[Kikoboy]

It’s a good point. I have sand, so it’s part of my monthly maintenance to vac the sand through a filter sock. It’s an extra chore, but I still find it much easier to add this than doing the full water changes+vac.

Yup I second that. ATW is great for the water change itself, but I still have to suck out the detritus from sump
Manually , and from the tank if you are going bare bottom.

 

[Jax15]

So to mirror that I'd setup a 7G a day water change cycle over a 24 hour period which should be doable with an Apex DoS.

One thing to keep in mind, the Dos is VERY loud. I was surprised by just how loud. So 24 hours at 7 gallons a day will be screaming loud. You may want to rig two so you can have them each run closer to half speed, or set them up away from your living space. I ended up just running mine at night since it’s setup away from the bedroom, and doesn’t bother me at all now.

 

[schuby]

One thing to keep in mind, the Dos is VERY loud. I was surprised by just how loud. So 24 hours at 7 gallons a day will be screaming loud. You may want to rig two so you can have them each run closer to half speed, or set them up away from your living space. I ended up just running mine at night since it’s setup away from the bedroom, and doesn’t bother me at all now.

I use DOS for AWS. I stagger them so that only one runs at a time (one starts-ends 00:00-23:50, other starts-ends 00:05-23:55). This cuts the noise level in half. Of course, the more water you move in a day, the louder the pumps.

 

[biecacka]

I do AWC, and here is the biggest thing I’ve noticed in my tank. With AWC I am less likely to siphon the little sand I have, and blow off my rocks as I used to with regular water changes. BUT I was not the most regular with manual water changes so it’s about a wash for me. Plus I put in more pumps for flow and that helps keep as much debris from settling as before.


corey

 

[Spieg]

This is def true, and part of the reason why 2% changed daily doesn’t actually equal 14% weekly, for example (Prob more like 10% net). It does add stability overall though.

I'd say that stability is debatable... perhaps more stable in a newer tank, or in the hands of someone new to the hobby (or those unable/unwilling to monitor and adjust dosing or do proper filtration maintenance), but my tank parameters are quite stable without any water changes.

 

[ckjhill]

I am seriously considering buying this one.

In fact I posted about it this am. How do you have your reservoirs set up? I need to figure out a way to do it vertically next to the tank, because under the stand and through the wall are not an option.

2 pumps burnt out on me in one month..

 

[Devaji]

I am gonna do it on my new RS 650P.
in the next year I hope to have a very large FOWLR and I might try a water less "triton" style set up....we shall see

 

[weamdog]

I've had an AWC running for about 6 months. I'm not a big fan because I have a 260g system and can only change out about 1-2g at a time from my sump before my return pump starts sucking air. I do like the ATO part, but I've found that if you're running a DC pump and vary the speed over the course of the day you run the risk of topping off during high flow periods and chaning out 5g of water with 2g. Things can get out of whack quickly. I've had a couple times when my sump was within 2 inches of overflowing so no more auto changes for me, I do it manually through the AWC but still takes too long since my water is gravity fed from garage (saltwater flows much slower than RODI).