Water changes with DOS

[Radman73]

Y’all are soooooo helpful. I understand what @CC13 is saying.... nothing lasts forever, and it is a movable part that is absolutely gonna break or wear out at some point. But if I could get a year’s worth of daily 2-3 gallon water changes out of it, it’d be well worth the cost. I too have back and knee issues...part of aging I guess... and a life around horses..... so having to not drag and lift huge things of water all the time is appealing. Heck.... if I could do small daily water changes like that, I might try to go sockless!

Keep in mind, the heads and tubing are all replaceable. It's not like you'd be buying a new DOS all the time. The motors I would expect to last a long while, especially assuming you'd use it on your 60gal tank. A half gallon per day would probably be sufficient.

Is there a reason you'd want to do 2-3 gallons per day on a 60? Or do you have a larger tank you'd be using it on?

 

[Epic Aquaculture]

I can't speak to longevity, but I also just set up an AWC using my DOS. 1.5 gallons a day on my 180 gallon. I love it, and it is working flawlessly.

 

[DangerDave]

I’d echo the volume questions. Mine seems to be going well, 220ish gallons of water, 3 gallon per day change. At around 4 or 5 gallons per day, the DOS unit starts to move much faster, scared me the first time I did it lol. I didn’t see any difference at 5 gallons, so I dialed it back.

I did have to replace a head once for a tube leak, but once I replace the tube do I’ll have a spare!!

Dave

 

[BestMomEver]

Keep in mind, the heads and tubing are all replaceable. It's not like you'd be buying a new DOS all the time. The motors I would expect to last a long while, especially assuming you'd use it on your 60gal tank. A half gallon per day would probably be sufficient.

Is there a reason you'd want to do 2-3 gallons per day on a 60? Or do you have a larger tank you'd be using it on?

No... no reason. You’re right... 1/2 to 1 gallon a day should be more than sufficient.... maybe 2 if I fed heavily.

 

[Radman73]

No... no reason. You’re right... 1/2 to 1 gallon a day should be more than sufficient.... maybe 2 if I fed heavily.

The main reason I asked was I started out doing .5gal/day on my 60. Things were fine, but for some reason I decided to bump it up to 1-1.5gal/day thinking more was better and the tank went downhill. .5gal/day ended up being the sweet spot, at least for me. Sometimes too frequent or too much volume water changes are a bad thing.

 

[BestMomEver]

If that’s a real screen shot of your Apex dashboard, I have to say, I feel so much better. My salt probe always reads high like yours, as does the ORP. I also fight my pH. Mine seems to hover around 7.8... often lower... never above 8.0 Frustrating...

 

[BestMomEver]

The main reason I asked was I started out doing .5gal/day on my 60. Things were fine, but for some reason I decided to bump it up to 1-1.5gal/day thinking more was better and the tank went downhill. .5gal/day ended up being the sweet spot, at least for me. Sometimes too frequent or too much volume water changes are a bad thing.

Good to know... thanks!

 

[Greybeard]

Y’all are soooooo helpful. I understand what @CC13 is saying.... nothing lasts forever, and it is a movable part that is absolutely gonna break or wear out at some point. But if I could get a year’s worth of daily 2-3 gallon water changes out of it, it’d be well worth the cost. I too have back and knee issues...part of aging I guess... and a life around horses..... so having to not drag and lift huge things of water all the time is appealing. Heck.... if I could do small daily water changes like that, I might try to go sockless!

Neptune is, in fact, advertising and targeting AWC with the DOS. Any mechanical device will break eventually... How long with the DOS pump last doing small daily water changes? We'll have to wait and see. Mine has been changing 1.5 gallons a day since November. So far so good.

Specs show DOS pump max at 250 ML/Min. There's 5678ML in 1.5 gallons. That means it should take about 23 minutes per day to do my AWC. 5000 minutes / 23 minutes per water change give us 217 water changes before failure. About 7 months.

Ask me again in May

 

[MSB123]

If that’s a real screen shot of your Apex dashboard, I have to say, I feel so much better. My salt probe always reads high like yours, as does the ORP. I also fight my pH. Mine seems to hover around 7.8... often lower... never above 8.0 Frustrating...

It is.
My probe reads high unless I calibrate it every 3 months or so. (Which I haven’t done, its due this weekend)
My ph probe reads low because my ph is actually low, (try re calibrating yours, its a big improvement)
Orp has always been like that

 

[BestMomEver]

I

It is.
My probe reads high unless I calibrate it every 3 months or so. (Which I haven’t done, its due this weekend)
My ph probe reads low because my ph is actually low, (try re calibrating yours, its a big improvement)
Orp has always been like that

I’ve tried recalibrating and it didn’t work.

 

[DangerDave]

It is.
My probe reads high unless I calibrate it every 3 months or so. (Which I haven’t done, its due this weekend)
My ph probe reads low because my ph is actually low, (try re calibrating yours, its a big improvement)
Orp has always been like that

Watch your temp probe also. Mines been drifting a couple degrees recently. I'm not sure if I need to replace it. If it wasn't for my chiller kicking in (glad I left it on) I may not have noticed until the tank started suffering. I'm going to take it out and give it a good cleaning this weekend.

 

[Radman73]

I


I’ve tried recalibrating and it didn’t work.

By chance, do you live in home built within the last 5 years, maybe 10? Homes are tighter now, allowing less air exchange and causing internal air to have higher levels of CO2. This is why some people, me included, run an external air line to their skimmer. Mine helps, but only a little. I crack my office window open almost all the time now as that helps the most. When we have a large number of people come over to the house, I can see my ph drop

 

[OriginalUserName]

Yes and yes. Not having to lug buckets around is worth $300. I mix a big tub of saltwater in the basement and tell the DOS what to do. I can do my regular 10% weekly or do larger changes as needed. I would not go back to having a tank without some type of auto WC. It was tolerable in my 29cube, but now at 140 gallons that would mean 3 buckets just to get to 10%.

Right now I only need to carry RO water buckets but soon I'm going to get around to routing my RO output directly into my FW reservoir by the thank.

 

[Dburr1014]

Just following the thread. I have often wondered about doing AWC. why 2 pumps though? I would think you can dose with 1 and have it trickle out to the house drain/septic on the other end.
Possible? No need to calibrate them to be perfect pairing. (nothing is perfect)

 

[Radman73]

Just following the thread. I have often wondered about doing AWC. why 2 pumps though? I would think you can dose with 1 and have it trickle out to the house drain/septic on the other end.
Possible? No need to calibrate them to be perfect pairing. (nothing is perfect)

That could get tricky. If you have the drain in your sump, if you lose power you lose however much water flows into the sump, not a good thing. If you have it drain from the DT or overflow, then slight differences in flow can create slight differences in DT height, again causing water to flow, and ATO to kick on, lowering salinity, perhaps drastically, over time.

If the DOS pumps are off even as much as 5ml per day, you salinity change would be very, very slow.

 

[CC13]

Just following the thread. I have often wondered about doing AWC. why 2 pumps though? I would think you can dose with 1 and have it trickle out to the house drain/septic on the other end.
Possible? No need to calibrate them to be perfect pairing. (nothing is perfect)

That's what I do.

APEX turns top-off to off
pump 1 drains the sump to the 'low' level sensor and turns off
Pump 2 pumps from the fresh RO/DI into the sump to the 'high' level sensor and turns off
APEX turns top-off back on

You never have to worry about salinity as long as the fresh salt mix is matched to your tank.

 

[Greybeard]

That's what I do.

APEX turns top-off to off
pump 1 drains the sump to the 'low' level sensor and turns off
Pump 2 pumps from the fresh RO/DI into the sump to the 'high' level sensor and turns off
APEX turns top-off back on

You never have to worry about salinity as long as the fresh salt mix is matched to your tank.

That's one method... As with all things, there's positive and negative attributes to every method.

This one relies on sensors... sensors can fail. You also can effect skimmer performance, if the skimmer section of the sump is affected, and you can't remove so much water at a time that it affects your return pump. None of those are terribly difficult to overcome, but some thought should go into it.

The DOS method is to pump in and out at the same rate. Sump volume never changes, so skimmer, ATO, return pump, etc are not affected. Salinity should not be affected, though if the pump speeds are mismatched, it could affect it slightly. No sensors to get stuck... though I do have a high level sump sensor and a low level reservoir sensor in place. They're just alarms, though.

As with everything else in this hobby, there's many ways to be successful. So far, I'm really liking AWC's... but who knows. In a year or so, I may decide to go a different route

 

[CC13]

That's one method... As with all things, there's positive and negative attributes to every method.

This one relies on sensors... sensors can fail. You also can effect skimmer performance, if the skimmer section of the sump is affected, and you can't remove so much water at a time that it affects your return pump. None of those are terribly difficult to overcome, but some thought should go into it.

The DOS method is to pump in and out at the same rate. Sump volume never changes, so skimmer, ATO, return pump, etc are not affected. Salinity should not be affected, though if the pump speeds are mismatched, it could affect it slightly. No sensors to get stuck... though I do have a high level sump sensor and a low level reservoir sensor in place. They're just alarms, though.

As with everything else in this hobby, there's many ways to be successful. So far, I'm really liking AWC's... but who knows. In a year or so, I may decide to go a different route

You are correct actually I turn both my skimmer and the ATO off... forgot to mention the skimmer part.

Again, I do larger water changes (usually 50+ gallons at a time). I don't perform them each day, but I could if I log-in and run the water change schedule.

 

[thabizness]

I have had the DOS since it came out. I have used them for Alk/Ca dosing. Its been used for daily AWC. I have dosed NOPOX and Acropower from them. I have even used it feed CaRx and Kalk reactors. That being said I also had a one button water change using optical switches and two PMUP's to do water changes too.

All that being said I am using one of my DOS units now for AWC (I tinker alot) It doesn't really matter how its done (the 2 PMUPs and 2 floats is cheaper) just that if you don't like to do water changes set up a system to do it for you. With the DOS AWC I don't worry about skimmer level or ATO like I did with the two pumps version. The DOS really makes it too easy but comes at a cost of the DOS unit AND the occasional head replacements.

 

[rioreef]

Neptune is, in fact, advertising and targeting AWC with the DOS. Any mechanical device will break eventually... How long with the DOS pump last doing small daily water changes? We'll have to wait and see. Mine has been changing 1.5 gallons a day since November. So far so good.

Specs show DOS pump max at 250 ML/Min. There's 5678ML in 1.5 gallons. That means it should take about 23 minutes per day to do my AWC. 5000 minutes / 23 minutes per water change give us 217 water changes before failure. About 7 months.

Ask me again in May

Your math is off. According to Neptune the stepper motor has expected life of 5000 Hours. At your calculated 23 min per day you are safe. The heads will wear and that will be the maintenance.