Our mission

Fresh Water Top Off

screebo

screebo

Guest
BARcard
A while back........a LONG while........I bought a JBJ auto top off set up for a very affordable price. I think it was about $90. After a while I noticed that it's float switches would occasionally stick from salt and precipitate build up. I got in the habbit of grabbing the switch and it's hanger and dunking it in the sump, swishing it around a bit then placing it back in place. If I did not perform this operation at least every other day, the switch will stick and the sump overfills. Hmmmmm.

It may have been Gresham that casually suggested to me that I consider a Tunze Osmolator. Well, that's sure a fancy name for an auto top off. :) I saw that they were about $200 bucks and thought...."too much". The other day I just got tired of swishing the float switch and picked up a Tunze Osmolator at Neptune. Instead of a float switch, the active level control is performed by an electric eye. When I first installed mine, it did not seem to be performing correctly. It would fill beyond the level of the eye and trip the emergency cut off mechanical switch triggering the audio alarm. Hmmmmm. I was just about to contact Tunze and I seems to resolve the issue by moving it to different locations in the tank.

Take away message: Spend the extra bucks and get a more dependable method of evaporation control using the electric eye method.

Take away question: Has anyone else using a Tunze Osmolator had the intermittent sensor triggering issue?
 
A lot of people have that issue. I talked with the guy at Tunze and one of the issues is that the unit has a 10 second 'delay' (I'm sure there's a better term for it) where the pump must be on. Meaning - the pump must be triggered for 10 seconds until it turns off. I played around with it a bit and this does seem to be the case. For my small tank, I added a mini flow regulator/ball valve. The sensor also needs to be in a place with minimal air bubbles and non-choppy water.
 
To solve your salt buildup problem (and mine) I just put the outlet of my topoff such that it pours down on top of the float switch and rinses it off. Tends to keep the float from killing right away as well, granted an aqualifter filling a 20g sump wouldn't turn off right away anyways. Seems to keep the salt creep down.
 
Great input, Con and Mitch. Brilliant idea about allowing the fresh water input rinse the float switch. Since I've got the Tunze on line, does anyone need a JBJ top off? I've got two of them with switches etc. Just let me know if you want to give the JBJ set up a go. Thanks, Con for what I almost deduced that it seemed to operate inconsistently at first then got more stable. I had it too close to the return as well and was collecting some bubbles that affected it too. I "think" we're good now but with anything that can potentially flood the kitchen, I'm cautiously optimistic. :)
 
Other ideas:
1) Use a simple mechanical float valve as an emergency shutoff.
Cheap.
So if switch fails, and it starts to overflow, the float valve will stop it in another inch or so.

2) Start the flow based on a timer, not a float switch.
Basically, every couple of hours, start it, and run until "full" float switch is triggered.
Only works if you have a micro controller handling the top off.
One less thing to fail.
Plus, you can tune it to optimize for certain pump duty cycles.
 
I've been slowly getting my thoughts together on an ATO and wanted to put in an emergency shut off float switch, but where would you buy something like that pre-assembled?
 
Just a note that you may want to have the emergency be a different technology from the main ATO.
Meaning : If your ATO is based on electronic switches, a mechanical float valve is a good backup.
Largely because that way the mode of failures is different, and less likely to occur at the same time.
But also because possible user error / misunderstanding on setup could be the same for both.
 
Update: My Tunze is working like a champion. It's maintaining such an even level of my sump that my skimmer is working about 100% more efficiently. It has a float switch override in case the optical sensor goes south. The secondary float switch is mounted on the same magnetic holder that the optical sensor is mounted on. Very clean set up. An alarm sounds very loudly when it's activated. I had to move the optical sensor a few times to get it to operate properly. Not cheap, ($200) but a very good investment!
 
iCon said:
A lot of people have that issue. I talked with the guy at Tunze and one of the issues is that the unit has a 10 second 'delay' (I'm sure there's a better term for it) where the pump must be on. Meaning - the pump must be triggered for 10 seconds until it turns off. I played around with it a bit and this does seem to be the case. For my small tank, I added a mini flow regulator/ball valve. The sensor also needs to be in a place with minimal air bubbles and non-choppy water.
Click to expand...

Being very new here, it would be ever so helpful if someone else were to admit that the valve idea, while blindingly obvious in hindsight, did not immediately occur to them, as it did not immediately occur to me. :)

Thanks iCon, you've made my day.
 
I've been looking for an ATO solution and the Tunze seems like the best bet short of going for a full controller system (someday....). I found this article on ReefCentral about converting your Osmolator to be a full water change system. Quite an ingenious setup. I'm now even more keen about the Tunze as an ATO & W/C solution. If only there was a way to work in two part dosing.....
 
Read Kinetics build thread to see the dangers of 'auto water changer systems'
 
I also got fed up with all my ATO schemes. I finally bought a Spectrapure Ultimate Top Off (or whatever) unit. It was pricey, but it's worth it not to have such hassles. It uses some kind of air-pressure switch to check levels ... very easy to use too. I run mine into my kalk-mixer so that kalk is returned to the sump, so I can't do a "rinse off", however I don't see much salt build up on the sensor tube. It has a backup float shut off. I feed mine from a 5 gallon water bottle which I don't think will flood the extra capacity of my sump.

It's painful to pay up at front, but considering the wasted money of other "schemes" (medical doser, drew doser - which is good, but not for top-off or continuous run) it is worth it to just start off with a good unit. Once you have it running to your satisfaction, you will feel much better when you go on vacation!

V
 
Screebo,

Happy New Year.

Thank you for your post on the Tunze T/O problem you experienced.

I just put one in my sump and had the same problem.

I spoke with Kris who suggested the Tunze; and he was surprised I was having a problem with it.

Tuesday, I'll move the sensors away from the mechanical pumps. Hopefully that will take care of it.
Thx again :D
DSC_0377.JPG


UPDATED 2/25/14

I'm happy to report: Today, I wiped down the Tunzi sensor and all is well. This is a nice top off system. My less than 1 year old ATO.com T/O system leaked voltage into the sump tripping the gfci. The owner Paul?, tried repairing it, and after receiving it back, it was still leaking. I hope Tunze is better at customer care (should I need it). I bought this on sale at Marine Depot for apx $190 with tax and free shipping.
 
Last edited:
You must log in or register to reply here.
Back
Top