$19.99 Top Off System

[Shallowwaters]

Here's a top-off system I built for my 150 Rubbermaid sump after fooling around with two commercial systems. (I am not going to bash specific products here.)

To achieve stable salinity, everybody has to choose between four types of top-off systems. (did I miss anything?)

Manual - Cheap, good for small volume sump, but time consuming & bad for vacations
Direct connect float Valve - Moderate price, no pump required, big & Small sumps, but requires fixed plumbing and they can stick!
Mechanical Valve switch - Can be expensive, more consistent result, not good for large volume sump**, and can stick!
Dosing System - Usually most expensive, trial & error required, but superior result


In my opinion, the best compromise is a mechanical valve and there are many to choose from...Ultralife Float Switch $60 (vertical mechanical Switch), Tsunami AT-1 $60 (vacuum operated), the Tunze Osmolator $162 (dual optical sensors)

All of these products sense the water level and control and electrical pump. Unfortunately, each product has a course grained setting for the water level. In some cases a variance well over one inch is required and in the best case it may be 1/2 inch. These type of products work very well for under-tank sumps or sumps of moderate size. Unfortunately, the larger the sump, the less effective these mechnical devices are at maintaining a constant level. The problem is that, big sumps have a larger the surface volume and they require signifant volume change before commercial systems trigger top-off action.

If your sump large (50 gallons+), then a 1 inch drop may equal 4-5 gallons or more and this could be a signficant percentage of your overall volume. And if something goes wrong for more than one day, the problem compounds.

Here is a CHEAP and (so far!) effective method at addressing these problems...

Ingredients to the Solution
1- Aqua Lifter Vacuum Pump AW-20 by TOM $12.00
This pump delivers 0.22L/minute or 3 1/2 gal/hr or just under 1 gal in 15 minutes
http://www.marinedepot.com/md_viewItem.asp?idproduct=KTALP
2- CVS Pharmacy Lamp Timer - w/ 15 minute settings or 96 daily settings $6.99
(this is the only grounded plug timer I have seen with 15 min increments)
(here's the exact same product for a lot more money http://www.hydroponics-garden.com/sunsundualti.html)
3- Sufficient airline tubing $.50
4- Duct Tape for holding pump if necessary (priceless)


For the most part, this top-off system requires little explanation. But here are a few tips.

- My system needs about 4 gallons per day, so I set my timer for 4 15 minute increments per day during with 3 during light cycle and 1 during night.

- Pump input line, that hangs in my RO/DI resevoir is cut short so that it can only pump a certain maximum and cannot drain my 40 gallon resevoir thus causing a flood.


Benefits of this system-

- Aqualifter pumps are cheap and yet dependable
- Failure of the pump or timer do not cause a flood!
- "Fine" control can be set to allow dosing from another system at night with Kalkwasser


Hope this helps somebody, but I'm also interested in new suggetions.

Any other ideas out there?

 

[smcnally]

I only see one problem with your plan. Evaporation changes constanly. It varies depending on the temperature of the room your tank is in, the humidity level of that room, your water temp, the lights being on/of, etc. I think what you are doing will probably work for the most part, but it will probably either slowly give it a little too much or too little. Maybe it will do both and even out in the long run.

 

[wrassefan]

I've been using a similar system but with a digi timer for more accuracy. I've been using it for about 8mo. due to mostly laziness in hooking up a float switch. The evap rate does change from summer to winter but not a huge amount. You do need to adjust the topoff (sometimes weekly) but overall it has been great. I keep a rubbermaid 20gal.tub next to the tank with limewater. You might want to recheck the delivery rate with the aqualifter. I think I got 3.5gal/hr with my calculations and then in actuality...it was almost 3 gal./hr. Also, I have mine topoff 5 times a day for anywhere from 5min.-10min. for more constant salinity. HTH...I think adding a floatswitch in conjunction with the timer would be a good safety only because then the floats won't work without the timer on.

 

[Piscevore]

The thing that ticks me off is that I just bought one of greg's super fancy peristaltic dosing pumps, to do just this, because I wasn't sure what else to use. I could've bought a lot more aqualifters had I know they existed and just thrown them away periodically. D'oh. Kalkwasser, Here I come!

 

[Shallowwaters]

smcnally, I guess you are right about changes in evap rates. I guess it's a problem even if you spend $300 on a dosing pump.

I forgot to mention that I had to invent something. I tried to modify the commercial products, but they simply will not work for a big sump if you want a consistent level.

My digital timers only have 4 cycles per day and I thought I would need more when I set this up so the CVS timer is a good cheap answer.

 

[Piscevore]

The only thing I would add is either a float or a high water sensor just in case everything else doesn't work.

 

[One Eye]

I just finished putting together a 30 gal top off, centered between 2 systems and supplying them both. I used the Kent Marine http://www.marinedepot.com/md_viewItem.asp?idproduct=KM1675 float valves in each sump. I built a 3/4" plywood box 16" high to place the 30 gallon rubbermaid bin (resevoir) on. The system works on gravity so there's no pumps. My rodi goes directly to the resevoir, I drilled a hole on each end of the resevoir, about 2" up from the bottom and used 1/4 tubing to the float valve in the sumps. I put a maxi jet in the resevoir to make mixing kalk nice and simple.

 

[Shallowwaters]

One Eye,
Sounds good. Can we see a picture of yours?

 

[Piscevore]

I've got to tell you Darren, I would not trust 1 mechanical valve against 30 gallons of death and gravity. Gravity -always- wins. I'd rather move it up hill in small doses, rather than down.

This is just my neurosis, but a powerful one...@!

 

[jackie]

Darren and shallowaters they both sound like great setups, but when it comes to water+float valves+murphy's law, I get heart failure. I'm still doing the gravity drip method myself. 3 times this week I was making water and forgot about it, 3 floods. At least my kitchen floor is clean.

Post pics though, I might get brave and try it. If I go to a bigger tank, I'll need something bigger than 5g water bottles.....

 

[Armando]

After having a couple of Ultra Life float switches failing and causing floods, I've decided to no longer use any sort of float switch, just a waste of money, as they seem to break sooner or later. I'm now using peristaltic pumps and it's working well for me. IMO IME.

 

[jackie]

So how do these peristaltic pumps work? The internet shows a pic of a pump and two hoses, but not how it's set up. Don't get too techy, I confuse easy

 

[Armando]

Jackie work like any other pump. but like in slow motion

 

[denvig]

I used the Kent Marine float valves in each sump.

Daren I have used this system before and when you use Kalk. It will eventually build up on the valve and hold it open (It will happen) the problem is you never know when. And 20 or 30 gallons of fresh Kalk water?. Well you know what that can do. I use this system now and it works flawlessly keeping the level in a 35 gal sump at no more than ?? from set point.

http://www.reeffanatic.com/products/float-switch-and-level-control/level-controller.asp


I use it with one float switch that controls the level in the sump with the other switch also in the sump as a back up to shut of the MaxiJet in the reservoir incase the first switch hangs up.

 

[jackie]

This is what I got off the internet... The peristaltic pump operates by compressing a plastic tube between an element attached to a rotor and the internal wall of the pump case or housing. Fluid in the tube is forced from the inlet side of the pump toward the discharge by the squeezing or compressing motion of the element on the rotor of the pump as it rotates.

So, the slow motion is somehow connected with the compression part.

 

[Armando]

what i meant is that these pumps deliver a much smaller GPH. Actually they are usually rated in GPD instead. I don't know how they actually work.

 

[One Eye]

The float switches I'm using are pretty simple. When the "balloon" gets pushed up by the water level it pushes a piece of rubber against the hole and stops the flow...the flow is only a fast drip at best. Either way even if the float switches let go it would be a continuous drip into both sumps. Both sumps are able to handle the excess water...and as a back up when I built the stand I set a sheet of 1/2" plywood down, then nailed a 2x4 box around it. I put the legs of the stand on top of the 2x4 box. I wrapped the inside of the box (and the plywood) with ice and water shield, making a 3 1/2" x 96" x 24" Bath tub to catch any spills. The sumps and top off are in the bath tubs.

Anyway...I hope they work. I just set them up last night, seemed pretty fool proof to me

 

[Shallowwaters]

Jackie, Aqualifter pumps are a cheap form of a peristaltic pump. They have one setting and go slow. The have the added benefit over other pumps in that they deliver a consistent flow because they are "pulling and pushing" water in controlled amounts. But you can't use them for dosing additives - they pump too fast for that.

A peristaltic pump is the ideal dosing pump, but I had already spent over a hundred bucks on level controllers and decided to try my hand at the problem with stuff I already had. It works great for a large sump where the Tsunami product was too insensitive for a big sump.

Denvig - that's great you get a 1/4" inch from Reeffantic's controller. I might try that one some day.

 

[jackie]

I kind of get it, I would have to see them working so I can put it all together. I'm a 'show and tell' person when it comes to this stuff because it seems complicated. Thanks for explaining it guys. I'd like to try something like that at some point, if someone else builds it .

 

[Piscevore]

peristalsis is like peanut butter in a balloon, or tooth paste in a tube. You kinda squeeze and slide, and viola!, stuff moves. Its also how we swallow.Reverse peristalsis=vomit! Flexible tubing is gyred and it squeezed to move fluid in our peri pumps. I am using a double headed medical grade kole parmer nuclear age peristaltic dosing pump (from greg hiller) to push kalkwasser into my two tanks. It is kinda noisy. It needs to run quite a bit to manage my top off needs.