How to automatic mixing water

[Lampshade]

The issue with drums is finding a food safe drum so that the Bearings aren't exposed to the salt, and also made of stainless. Anything else would be pretty scary to use on the tank :S.

My opinion would be a simple hopper with a valve. You need something that will seal off the salt when not in use, if it's in the same area as mixing water, the humidity will make it a salt block in no time. If you made a desenct sized hopper with a small outlet, even a 0.5" opening you could open/close that to add salt. Program it so that the hopper is open for a short period then closed for 20+ seconds to allow the salt to mix. Make it cycle whilever your salinity is low.

[Cranky When Wet]

All very valid points...

With that in mind, Lapidary tumbler drums are typically isolated from bearings... I wish I could comment on the grade of the poly/vinyl liners but I've never tested the units for SW applications.

There are a number of manufacturers worth speaking with i.e. Thumlers, Covington or Lortone (just don't look at the cheap units - they are trash and don't last.)

Covington does make a "Hopper-type" unit for polishing gold/silver castings... Here's a link to see what they look like...
http://www.covington-engineering.com/deluxe_tumblers.htm

One might look at their "Vibratory" Tumblers as well? Tho I'd be concerned about heavier elements sinking to bottom and causing tank troubles... http://www.covington-engineering.com/vibrating_tumbler.htm

I'd personally lean towards Covington for getting answers to technical questions...

I do like your thoughts on using a hopper sporadically :-)

Bunny

Originally Posted by Lampshade

The issue with drums is finding a food safe drum so that the Bearings aren't exposed to the salt, and also made of stainless. Anything else would be pretty scary to use on the tank :S.

My opinion would be a simple hopper with a valve. You need something that will seal off the salt when not in use, if it's in the same area as mixing water, the humidity will make it a salt block in no time. If you made a desenct sized hopper with a small outlet, even a 0.5" opening you could open/close that to add salt. Program it so that the hopper is open for a short period then closed for 20+ seconds to allow the salt to mix. Make it cycle whilever your salinity is low.

[sphelps]

Super saturation is your answer. Setup another water top off using something like a 29 gallon aquarium. Drill and install an overflow in the aquarium and mount the aquarium above sump level. From your fresh water top off use another pump or solenoid depending how it is setup. Send one fresh water line directly to the sump (Fresh top off). Send the other fresh water line to the 29 gallon aquarium (salt water top off). Plumb the overflow into the sump so when fresh water is added to the 29 gallon it overflows and drains into the sump. Next fill the 29 gallon with water and add a full bucket of salt, use a small powerhead to keep the water circulating and even a heater if you wish. Now setup your controller to either activate the fresh water or saltwater top off based on the salinity measurement in the sump. The salt water added will be supersaturated but it won’t matter as the controller will simply cut it off once salinity is restored in the sump. This will maintain salinity so to auto change water simply hock up a pump and timer in your sump to pump water to a drain. Depending on the controller you can even set an alarm for low salinity which will prevent the pump from removing water so it won’t change water if salt is needed. And when salt is needed simply add another bucket to the tank, doesn’t get any easier. Done this exact system with a profilux before, it was dope!

[russp]

I may have an idea for you , I own a convenience store & I have a hot chocolate machine that has a food grade plastic hopper with a plastic auger in the bottom . It is driven from the back by an electiric motor & coupler system. the hopper would probably hold about 2-3 lbs of salt at a time . I will try to post a picture for you if interested.

[Bloodasp]

Problem with supersaturated solution idea is the amount of maintenance you have to do to the ATO pump. As It doesn't run continously so if the water evaporates your ATO will eventually clog with salt pretty fast since it is supersaturated.
I'd go with the auger idea, just what type of material it should be made of would be the issue, plastic wouldn't work as the salt would act like a sandpaper and would wear the auger out in no time.

[sphelps]

Originally Posted by Bloodasp

Problem with supersaturated solution idea is the amount of maintenance you have to do to the ATO pump. As It doesn't run continously so if the water evaporates your ATO will eventually clog with salt pretty fast since it is supersaturated.
I'd go with the auger idea, just what type of material it should be made of would be the issue, plastic wouldn't work as the salt would act like a sandpaper and would wear the auger out in no time.

Actually the way I described it this could not happen. The salt water top off pump will only pump fresh water into a tank and then the saturated salt water overflows into a drain that goes to the sump. If you made the drain at least 1/2" there's no way it would clog, plus it's a drain and will be empty unless the top off is running.

Like I said this system was used on a reef tank for about a year before the entire system was sold off. No problems occurred during this time. A hopper system isn't really going to work as well as one might hope, it will cost more and can clog up if the salt is exposed to air. Ever left your salt bucket lid off before and ended up with salt bricks? Same deal. Even straight out of the box or bucket salt is often clumpy.

[Bloodasp]

Though I wonder if an auger made out of PVC material would work.

[golf nut]

I do like the supersaturated method but was warned against it for some reason when I posed a similar question, I will need to dig up the thread that is out there someplace.

A plastic auger wouldn't be that hard to manufacture, what size do you want?

[russp]

Here are a couple of pics of the hopper I was talking about . Not great but I think you can get the idea.[IMG][IMG][IMG][IMG][/IMG][/IMG][/IMG][/IMG]

[sphelps]

Originally Posted by golf nut

I do like the supersaturated method but was warned against it for some reason when I posed a similar question, I will need to dig up the thread that is out there someplace.

A plastic auger wouldn't be that hard to manufacture, what size do you want?

I think we've discussed this before and I remember my concern being related to whether the levels of elements would be affected in the saturated salt water. I did monitor the measurable levels in the aquarium which had this system and for the most part they remained stable. The tank didn't have any dosing or supplemental systems so the levels weren't always perfect but did remain within reasonable tolerances. Basically I didn't notice any difference in stability before and after the system was installed.