Water Treatment...any advice?

[Kiwi Phil]

I plant out 6-8,000 pots every week.
I have a total of 60,000 pots growing at any one time.
I throw out approx 500-700 pots per week because they are effected by the diseases Phytophra or Pythieum. This in my case is a water borne disease.
I try to treat the water mannually, but over past years (10) it is a hit and miss affair.

I went out and purchased an electronic dosing unit from a Pool Shop.
It doses Chlorine (to kill disease) and Acid to balance the Ph (allows plants to take up max fertilizer in water = better healthier plants)
Question:
Has anyone used one of these units in their swimming pool, and if so, what did you find/learn was best way to operate system.?

I need to run a Ph around 7, so I set the unit to sence Ph and then dose asid to balance water to Ph7. Was going to use Acid in a 1 gal container (have 44 gal of 98% in shed and pump to decanter)

I need a Chlorine lever of around 4-5 ppm, which i think the instruction book tells me to set sensor and dose-or to 650milli volts.

I do have a clear instruction booklet, but if any of you have ever used this system to maintain a pool, then i need to know your experiences.

LIKE: sensors before or after pump: where dosing valves are best placed: does dirty water effect results:
There is nothing like personal experience, and I have NONE with these units.

Thanks in advance
Cheers
Phillip

 

[Kenneth Brown]

Re: Water Treatment...any advice?

I know it don't help any Phil but I gotta say- Can't nobody EVER accuse you of being lazy. Your business seems like it has you run ragged. I know who's tree I'm gonna bark at when I need help with the herb garden.

 

[Kiwi Phil]

Re: Water Treatment...any advice?

Thanks Kenneth,
My family all accuse me and Anita for working too long-an-hours, but when we do have a half day or so with nothing to do, we find we get bored.
Of course the family all line up for financial assistance, regularly, and "Anitas Little Black Book" is an interesting read.
I guess this is what happens (pitfall) when you do something you thoroughly enjoy.
I say this because this morning, Anita, who never ever swears, said to me "I am thoroughly F.....d of with this place at the moment", but she went out for 9 holes of golf at lunch time, won a $30 voucher, and is all smiles again.
Anyway Kenneth, thanks for the comment.
Cheers
Phillip

 

[Kiwi Phil]

Re: Water Treatment...any advice?

Here is a question for everybody.
I have installed this dosing unit. Had some problems which I will relay in a minute.

First, the chlorine levels are measured in Millivolts on the ORP (Oxidation-Reduction-Level or REDOX method)(which i believe is 1,000th of a volt) and the book tells me if i run at 650 millivolts, the chlorine will kill the bugs in 1 second. At 550 millivolts it takes 2 hrs.

All my hydroponic/grower mannuals tell me to guage my chlorine by 'parts per million', written as ppm .

[colour=red]I am seeking a conversion table that tells me X ppm euqals y millivolts or vice-versa, so i can do conversions quickly/easily[/colour]

Been through that conversion table some one put up years back but can't find this one.

Can anyone be of assistance.

This dosing machine is amazing. Its probe measures chlorine and ph levels every 3 minutes, and doses chlorine or acid to balance at levels I preset (hence I need to know convesrions as per above Question.)

Had some fun getting it going.
It is placed at the bottom of a 10,000L tank, and it wouldn't dose.
Solution is (took 3 days to work out)....it is designed for a pool and this unit sits above the pool water level.
...restrict (part close) the valve from the tank to make pump really pull, so when dosing unit switches on the force/speed of water in main pipe draws chemical INTO mains.
Previously, the large slow volume equalled force of chemicals from injector pumps, so nothing got injected. The 2 forces equalled each other.
Next surprise......my water balance is all over the place, and has been for last 10yrs......a real hit and miss affair. Always thought my ph was high, so added acid to pull it down.
Probes tell me ph is low, way low, which tells me my water is too acidic, and I am having a tough job getting it up.
Got it up from 5.2 to 6.6 but has to be 7. If i havn't got it by sunday, dumping tank and starting again.

Can anyone assist wilth millivolts/ppm conversions.

Thanks chaps
Cheers
phillip

 

[technostingray]

Re: Water Treatment...any advice?

Sorry Phil, this is just way over my head. I can help you find a cheaper starter though. :+ :=

 

[12Footer]

Re: Water Treatment...any advice?

.

Way over my head,Phil. And I think you may be breakiing new ground ,or writing the latest chapter in the "Chlorine Treatment for Horticulture" book. But i found this link on the net that may help.
------------------------------------------------From SW Florida, A proud member of iboats since March 25,2001
The old me

 

[tommays]

Re: Water Treatment...any advice?

I do look after and ULTRA pure water machine for Pharmaceutical use

Its very high output 50 gallons per min

We start with street water and filter it to 5 micron which is very cheep The UV section KILLS everthing else very nicely

Then .5 MICRON filters are not that costly eather tHEN .2 MICRON BUT last over a year very easely BUT COST ABOUT 150 DOLLARS

The system has a 400 ft loop to distrubte the water AND we just Bleach it once a week to be sure

We get a 0 TOC Pharmaceutical grade water

Tommays

 

[Kiwi Phil]

Re: Water Treatment...any advice?

Lets back up a bit here tommays....
Did I read it correctly.....you can filter water down to .5 microns for the cost of a US$150 filter, and you put through up to 50 gpm.
That definitely has me interested.

I can get away with 80microns, (prevents any blocking of my micro feeders @ 2mm dia),which I can achieve with a standard Irrigation Disc Filter, but my aim was to use something like a DE (Daemetious (sp!) Earth) Filter which brings it down to 5microns.
I believe this will make the killing power of chlorine much more efficient.

Since I have got this system working (over past week) the chlorine has been doing a good job, and removed all algae from the tanks, so now all my disc filter picks up is sand granules etc.

My problem is water borne Phytophera and Pythium, which attack the roots of the plants belonging to the carrot family: ie corriander, parsley, dill, fennel.
The roots go orange, rot off, and the plant dies. Chlorine kills these 2 diseases.
That means, not only do I need steralised water in my 10,000L header tank, I need chlorine in the water to actively kill the diseases as the water passes through the growing tables and pass the plants roots. Too much chlorine, and that will kill all plants, so 2ppm is ok.
That is why UV and Ozone (o3) are out.

The ph is a major problem. No matter how much soda ash I add, it brings the ph up to over 7, (which is what I want), then over next hours is slides back to ph6.6, which means it is a bit to acidic, and that slows the plants ability to take up mutrients.
I am pretty sure I can over come this problem by myself. It must be just logic/mechanical.

Tell you what else I have learnt over past week. Everybody measures chlorine in ppm (parts per million) until they start using automatic sensors, then they measure it in millivolts, and there is no set scale to follow...
eg 650 millivolts at a ph on 7 gives a 2 second kill with chlorine, but once you vary the ph, then that 2 second kill time varies all over the place.
Rang the City Sewage Treatment Engineer, and he tells me easiest way is to formulate my own chart by recording:
1) the ph
2) the millivolts
3) the chrloine in ppm with a pool test kit

and over time I will have an accurate chart of how effective the chrloine is with variences of other 2 factors.
Does that make sence?

Sorry to bore you with these details, but would like some info etc on that filter you talked about.

My pump moves 40gpm, (and it draws from the bottom of the header tank, reads/doses chlorine, and puts it back in to the top of the tank) ,but I have had to reduce that down to about 15gpm.
Another bigger pump distributes water to the growing tables.
The booklet on this dosing system tells me it has 2x mini dose pumps, but I reckon that is wrong.....it has 2x solanoids...when the sensor reads low chlorine....the electronic control opens a solanoid for 5 seconds.....and the speed on the water going through the mains pulls the chlorine in like a venturi. It is a sealed unit, so I could be wrong.

Thanks tommays.
Cheers
Phillip

 

[ratracer]

Re: Water Treatment...any advice?

Phil -

Both Omni and GE make cartridge-based water filters that are are under $100 US plus the cost of the filters. Depending on the cartridge used, you can get capability from about 30 microns down to about 1 micron.
I don't know if these would be capable of handling the water flow rate you need or would otherwise be practical for your use but I figure a quick look couldn't hurt. Check out waterfilters.net and omni-water-filters.com to see what I mean.

I suppose you could consider adapting a cartridge-based pool filter, they have the throughput capability you need, but I don't know if the filtering capability would be fine enough.

 

[Kiwi Phil]

Re: Water Treatment...any advice?

thanks for that ratracer.
I have had a good look at those sites.
Goodness, I have one under the bench here at home, and never considered that style of unit until you raised it.

The commercial "Bag Filter" seems worth looking in to, so I will do that this week.
The cost of replacing filters could be an issue, but we will worry about that after I have checked them out.
Many thanks for the idea.
Cheers
Phillip

 

[tommays]

Re: Water Treatment...any advice?

Phil

Its 3 steps 5 micron ,.5 micron then .2 micron 7 filters in a houseing


the .5 dont cost that much its the .2 micron that cost 150 dollars BUT all the nastys are bigger then .2

US filter makes a lot of good houseings and filters when you go down to .5 and below you have to have o-ring seal filters and houseings

I will look monday at the prices and part numbers so you can get a better idea

Tommays

 

[12Footer]

Re: Water Treatment...any advice?

.

and over time I will have an accurate chart of how effective the chrloine is with variences of other 2 factors.
Does that make sence?

Sorry to bore you with these details, but would like some info etc on that filter you talked about.

My pump moves 40gpm, (and it draws from the bottom of the header tank, reads/doses chlorine, and puts it back in to the top of the tank) ,but I have had to reduce that down to about 15gpm.
Another bigger pump distributes water to the growing tables.
The booklet on this dosing system tells me it has 2x mini dose pumps, but I reckon that is wrong.....it has 2x solanoids...when the sensor reads low chlorine....the electronic control opens a solanoid for 5 seconds.....and the speed on the water going through the mains pulls the chlorine in like a venturi. It is a sealed unit, so I could be wrong.

Thanks tommays.
Cheers
Phillip

Phillip, I know zip about all of this, but for some odd reason, I'm intriqued with this whole thing.
I can't help at all, I'm sure. But something hit me right between the eyes in the quote above....

"it draws from the bottom of the header tank, reads/doses chlorine, and puts it back in to the top of the tank) ,but I have had to reduce that down to about 15gpm."
To me, that is treating previously-treated water,ergo, the chlorine dosing requirment WOULD drop for a while, until it normalises with usage, then it would stabilize.
Could you maybe run a secondary doser on the return once a new average loss table is established?
Just thinking out loud. .
------------------------------------------------From SW Florida, A proud member of iboats since March 25,2001
The old me

 

[tommays]

Re: Water Treatment...any advice?

This is the Aquafine UV sterilization unit which will run for years with very littel care

Model number: CSL4R
Serial Number: IS03 064-E DESE
Lamps (4): ZCSPL17491 $91.00
Sleeves (4): ZCSPQ3184 $72.00
O rings (8): ZCSPM4253 $ 2.00


These are US Filter part numbers i would think many people make them like Pall ect

FCPSF200F $ 8.36 5 Micron

It uses a T911529-432 HOUSEING

FCROO2005 $23.60 .5 Micron

FCWN020S2 $156.10 .2 Micron

The fine filters use a T910801-432 O-RING FILTER HOUSEING



I can keep a 17000 gallon pool clean enough to use the final filters with a small 1-1/2 hp DE unit


I would break it up into 2 systems

Your storage tanks would be 1 system with the DE unit and chlorine

And the a second system for final bacteria filtering before it reaches the plants


Tommays