DIY Gravity fed auto top-off system

[LunaReef]

Is anybody here using an auto top-off system that uses gravity to replenish your sump? We have the basement space to set up this type of system and are looking for some good DIY instructions. Found lots of good ones using switches and pumps.

For us, it will be a partially automated system, where the water supply comes from a resevoir instead of directly from the house water source. We were wondering what you are using for the resevoir itself and which type of float valve you have in your sump. This will be set up on a 58g display tank with an Oceanic I sump. Looking to hold 20g water in the resevoir.

 

[necco]

My new reef tank is going to have somthing along the lines of this, although I haven't tested it yet; theoretically it should work. I'm sick of filling the 5 gallon bucket everyday and dripping the RO/DI into the sump, its such a PITA.

Its pretty simple - I have a 1/4" john guest bulkhead on my RO/DI bucket, about halfway down (in case I need some water for water changes) the 1/4" line then goes into a 1/4" john guest valve (to stop the flow if I desire) then travels to my sump through a float valve. The water level should be at a constant level in this container (no up and down motion caused by mainly a durso) It should work, but if it doesn't thats what the valve is for . I bought the valves on ebay, they are all plastic componants and have been using one of them for somtime now without incident.

 

[LunaReef]

I'm sick of filling the 5 gallon bucket everyday and dripping the RO/DI into the sump, its such a PITA.

I hear that. It is a major drag.

Our auto top-off will be very similar to what you have drawn. I saw the float valves on the US Plastics website and thought that is what we'd probably need. We plan to plumb a spigot into the bottom of the reservoir also for filling buckets if/when needed. What type of container are you using for the 40g RO/DI reservoir? We were thinking of a heavy-duty Rubbermaid container of some sort...still unsure what to get though. Will we have to have circulation (a powerhead) running in the reservoir?

 

[JohnK]

I'll post some pics of my set up when I get home.

-basically RODI running on a timer, feeds a resivor near the tank (with it's own float valve to shut down the RODI auto shut off valve when needed).
-that resivor feeds float valves in the sumps of my display system and my frag tank system.
-That res also feeds kalk reactors on both systems (but that's a whole nother project...)

Super simple, no hauling buckets. The timer on the RODI is needed to prevent the auto shut off valve from constantly switching on and off all day. All the float valves I'm using are simple mechanical float valves (not float switches, level sensore exct, just simple float valves). This set up has been very reliable and needs no real maintence (nothing to clog up with only fresh water running through it).

 

[necco]

What type of container are you using for the 40g RO/DI reservoir?

Both are Rubbermaid Brute buckets. I guesstimated, but the 40g is actually a 44g.

Will we have to have circulation (a powerhead) running in the reservoir?

Yes, definitely have a powerhead of moderate flow in your RO/DI reservoir or bacteria will start to accomodate the walls and water of the container, and it will stink

 

[chew*]

I have about a 40 gallon holding tank for my RO and it gravity feeds my sump however you have to be really brave to run it like that. For instance the auto topoff works like a toilet plunger. It gets low it fills it gets full it stops but just like a toilet it can get stuck, unlike a toilet you will havea flood.

 

[JohnK]

Here's those pics of my simple set up. FWIW, I've used these kent style plastic float valves for years now. As long as it's only fresh water going through them they actually are quite reliable. If you drip kalk through them, they will clog constantly though.

Also, I don't get any film coat or smell in my top off res (without any pump to stir it) but the volume of the res turns over almost daily so that may be why I don't get a bacteria problem?

 

[JohnK]

.................

 

[JohnK]

and the solenoid so the RODI can be shut down with a timer (so it only runs long enough to cover daily top off plus a few minutes)

 

[LunaReef]

Cool, we will look into getting a Brute for our reservoir.

Yes, definitely have a powerhead of moderate flow in your RO/DI reservoir or bacteria will start to accomodate the walls and water of the container, and it will stink

I thought so but we have overlooked the obvious before so I figured I'd make sure.

 

[LunaReef]

This is a great and simple setup. I love that your RODI unit is on a timer and can fill the resi as needed on it's own...you cannot beat automation like that. We recently saw an awesome, somewhat similar setup at Clam Man's when we picked up the new tank. For us, we are going to only partially automate our system...at least to start with. My husband is going to plumb a water pipe right over to the reservoir that will have a manual shut-off. We are going to have to mark the resi and turn on the water every few days or so to top off the resi. In time, we may get sick of this and be brave enough to fully automate. Need to build up our plumbing confidences first. Even partially automated, it is going to be so much easier (and more stable) than it is now. No kalk reactors on our system so no worries about clogging up the valves. I can't wait to get it all up and running!

I'll post some pics of my set up when I get home.

-basically RODI running on a timer, feeds a resivor near the tank (with it's own float valve to shut down the RODI auto shut off valve when needed).
-that resivor feeds float valves in the sumps of my display system and my frag tank system.
-That res also feeds kalk reactors on both systems (but that's a whole nother project...)

Super simple, no hauling buckets. The timer on the RODI is needed to prevent the auto shut off valve from constantly switching on and off all day. All the float valves I'm using are simple mechanical float valves (not float switches, level sensore exct, just simple float valves). This set up has been very reliable and needs no real maintence (nothing to clog up with only fresh water running through it).

 

[JohnK]

Just get one of those alarm things that goes off when you have a flood. Everyone, has a RO flood sooner or later

 

[LunaReef]

Yeah, I am definitely going to invest in an alarm...for now it will go on the sump itself to warn in case the float valve fails. Later if we get brave and fully automate we will get another for the resi.

 

[Reef55]

I do something very similiar, although a two phase approach.

First phase is to make as much RODI water at a time as I can, automatically. The purpose of this is that roughly 20 gallons of RODI water are produced each "batch" (the reason for that is the longer the RODI is ran, the better the water coming out, and the more efficient the membrance becomes, which drastically increases the life of your filters). I have a 25 gallon rubbermaid container as my reservoir. I use a JBJ auto-top off, set to the mode that one float switch is the "filled" mark, and one is the "empty" mark. A solenoid is inline with my RODI unit, and is controlled by the JBJ. So basically, the JBJ unit monitors JUST the reservoir. When the level in the reservoir gets to the lower float switch, the JBJ opens the solenoid on the RODI. The solenoid stays open until the water level reaches the upper float switch.

The second phase is using a Tunze Osmolator to monitor the water level in the sump, and fill it as necessary from the reservoir (I need to use a powered setup here, because my reservoir is below my sump). However, my old setup had the reservoir above the sump, so I just gravity fed the reservoir into the sump via a Kent float valve.

 

[JohnK]

"(the reason for that is the longer the RODI is ran, the better the water coming out, and the more efficient the membrance becomes, which drastically increases the life of your filters)"

Yes, IIRC the problem to avoid is called "membrane creep". This why I have the solenoid and timer, but mark's set up is superior IMO because his probably makes larger batches of RODI less frequently, which should help to minimize or eliminate "membrane creep". My set up runs a cycle of about 3-5 gal everyday.

 

[JustDavidP]

My Set Up:

RO/DI (With ASO Valve) Mounted:

Flows to This barrel (20 gallon brute) with a float valve. The valve causes the back pressure to shut off the ASO on the RO/DI

 

[JustDavidP]

Waste water goes into the drain during the winter and to my koi pond during the summer:

The sump has another float valve that controls the level in the sump:

These systems can fail if you accidentially impede the sump valve. If you don't keep the opening clean of salt build up etc. I've only had ONE problem and that is when my son was "fishing" for starfish etc. in the live rock in my sump. He accidentially pinned the float and 20 gallons of RO/DI filled my tank and dropped my salinity somewhat.

Dave