Automated water changes

[Liam]

In a power outage the return pump will stop running. So as the plumbing and display tank drain down into the sump the water level goes up a few inches. All that extra gallonage from the display tank and plumbing will now overflow through your U-tube siphon, out of the sump, into the small bucket intended to hold the water-change water, and presumably onto Liam's nice new floor.

LOL ,yes and i have already had one disaster on my linoleum(sp).I kicked a bottle of purple primer over in the doorway,i had to replace that piece of flooring

 

[NateHanson]

I think i have come with a solution to prevent siphoning(which would be a problem beause my sump is lower than the level of my resevior).My idea is to pump the make up water through appropriately sized pipe until i reach the end of the horizontal run above the sump,i then plan to make the drop to the sump with a much larger diameter pipe and have the horizontal feed connect into the side of the vertical pipe with a barb connector.I would leave the top of the pipe open to atmosphere,this should prevent any chance of starting a siphon.
I hope anyway

That'll only work if the pipe goes above the water level of the reservoir at some point, and you install the vent at that highpoint.

If you put a vent above the sump, but the path of the water at the point of that vent is below the resevoir level, then you'll create a siphon that will empty your reservoir.

 

[Liam]

I think you got it. But it's not a "top off" it's an auto changer. SW for SW

hence the title of the thread"automated water changes"

 

[NateHanson]

I think you got it. But it's not a "top off" it's an auto changer. SW for SW

When I refered to the top off, I meant that since 20 gallons of salt water is going to end up on the floor whenever the return pump stops, that 20gallons will be made up by the fresh-water top off system.

The way I understand your waterchange system, when the main return pump shuts off (like in a poweroutage, or for cleaning) a bunch of water will flow out your bulkhead placed to drain the water change water. How does your system avoid that?

 

[Member No. 1]

That's one of the draw backs.

 

[NateHanson]

heehee. That's a big drawback!

 

[Member No. 1]

I'm gonna try and make the meeting on the 30th. We can talk it up then.

 

[NateHanson]

Sounds good! I'm apparently missing something! (unfortunately not a new situation for me )

Nate

 

[Liam]

That'll only work if the pipe goes above the water level of the reservoir at some point, and you install the vent at that highpoint.

If you put a vent above the sump, but the path of the water at the point of that vent is below the resevoir level, then you'll create a siphon that will empty your reservoir.

yes Nate it will be above the resevoir

 

[Matt L.]

Automated Water Change System

Okay,

I am a bit late to the thread (as is typical these days), but I employ a semi-automatic, passive water change system on my 90gal tank, the most difficult part being that the sump is contained underneath the stand and therefore very small.

My automatic water changer consists of a 35gal blue barrel drum with a bulkhead in the side. I take my time filling the tank with fresh salt water, and the tank has a heater and a Mag2 to recirculate. When ready to initiate the water change, I take a flexible hose (for like pool applications) and attach it to the bulkhead via a union and place the other end in the sump. I then take a MaxiJet1200 attached to some tubing and place that in the sump as well. The barrel must be fill to the bulkhead. I then simply start the MaxiJet to feed tank water to the barrel, which mixes with fresh water, and then exits via the overflow back to the sump. I turn my automatic level controller off during this process because there will be a slight dip in sump WS elevation.

This water change system is passive, in that it works by mixing the 90gal of dirty tank water with the 30gal of fresh water for a temporary system volume of 120gal, after which 30gal of mixed water is removed thereby affecting a 25% water change. It is not efficient in terms of water change volume, since 7.5gal are technically wasted when compared to performing an "active" water change (remove 22.5gal from 90gal and replace it). But, the benefits are that I simply throw the swithc and let it run overnight or however long, I can make up the water int he barrel and leave it indefinitely as it is clean and has a heater affixed with silicone on the inside. The best part is, the Mag2 recirculates up and out of the barrel and then down back in through the two bulkheads on the top. In this loop outside the barrel, there is a 3-way valve. I connect a hose to this 3-way volve and run it to the drain, and simply throw the switch so the Mag2 pumps to the drain instead of pumping back into the barrel. Even better, I don't have to interrupt the system to do this. I can leave all pumps running in the sump, etc., and it doesn't disturb the fish and corals by lowering the tank WS elevation. There is no reason why this system could not be made fully automated, although I prefer to keep an eye on it.

Perhaps I can take a picture of it when I get home,

Matt

 

[Piscevore]

this is an interesting idea matt