do meters

Is any one familiar with this meter.. https://www.ebay.com/itm/OAKTON-WD-35613-74-Water-Meter-Ion-6/231445717201?epid=4030335327&hash=item35e33d60d1:g:2WoAAOSw-W5UrN8X
I can't find any reviews.. It might be worth the $200 just to just to check what a bubble bucket, waterfall, and constant drip on hydroton, using an air pump, would yield.... Would be simple enough to do those tests in a 5 gal bucket and see the results.... On the other hand with my luck i'd be out $200 just to find out they would all be about the same.. If we get another 1200 , i may do it to satisfy my curiosity..

If you want to know if your water has maximum DO....
Once there is some movement in the water (so the upper layer of water gets refreshed on a regular base) there is maximum DO.
Getting maximum DO is extremely easy.
Getting DO-rich water inside the rootball once your plants get bigger... that is not always easy.

With constant drip on hydroton it seems to me that maximum DO is not important.
But maybe I do not understand that system.

Hydroton is the key to Waterfarms success... It's the interface with the large surface area of hydroton that adds the o2 to the water. I've never used an air stone.. I'm curiosity driven to verify the things i wonder about.. Percentage of dissolved o2 in hydroponics has become one of them.. There's always pissing over what's better. Theses are the three types of systems I can easily measure using buckets..
I've modified my WFs so they use the dripring to draw the water directly from a remote reservoir, gravity return.. The standing water column is better explained in my Waterfarm pimp thread.. I don't much worry about the root ball not getting enough o2. The water returns to the reservoir as fast as it drips on the root ball.. [5-6 gal hour] Water will not go around anything it can go through.. It will migrate through the roots, albeit at a slightly slower rate.. Doesn't depend on bubbles to add o2 to the center of the root mass.. Here's a couple of my modified Waterfarms

Cool thread. I just had a successful first run with a Waterfarm (unmodified) but I do want a larger reservoir to make life a little easier. I was concerned about DO levels though myself. Their larger system (Powergrower) only holds a half gallon more whilst still pumping out the same volume of water - I was looking to double water holding capacity of the WF and I'm not at all interested in adding an airstone or any other components.

If you buy a DO meter you will use it a couple times and then it will sit on the shelf collecting dust.

If you are concerned then I suggest a chemical DO test kit. Kits that will do 50 test only run about 60 - 80 bucks.

Keesje said:

With constant drip on hydroton it seems to me that maximum DO is not important.

Click to expand...

With the constant trickle of water and lots of surface area maximum DO is inherent.

Renfro said:

With the constant trickle of water and lots of surface area maximum DO is inherent.

Click to expand...

This is how I always assumed it to be as well - what are your thoughts on a larger res with the same volume of media and water being pumped?

Let me clarify, my thought was to simply stick the grow chamber on top of a larger res, all other things being equal.

With a drip / LECA system there is absolutely zero reason to worry about DO in the reservoir. The fact you are dripping the feed over the LECA causes it to become oxygenated as it is going over the LECA. It wouldn't matter what size reservoir you have. A circulation pump in the reservoir to prevent stagnation is all you require.

Now a larger reservoir is always good, not for surface area but for volume. Higher volume equals greater EC and pH stability. I run my flood and drain reservoir for a whole cycle, no change outs. I used to do that commercially on lots of 4x8's with 200 gallons per tray. Having the added capacity makes it easy to do.

Bet, thanks man - I will move forward with my plans then.

Renfro said:

Now a larger reservoir is always good, not for surface area but for volume. Higher volume equals greater EC and pH stability. I run my flood and drain reservoir for a whole cycle, no change outs. I used to do that commercially on lots of 4x8's with 200 gallons per tray. Having the added capacity makes it easy to do.

Click to expand...

But you did add water + nutes during that grow in your rez?
I mean: The 200 gallons where not enough for the whole grow, right?

Keesje said:

But you did add water + nutes during that grow in your rez?
I mean: The 200 gallons where not enough for the whole grow, right?

Click to expand...

It's automatically topped off every night via a float valve and I do maintain PPM. I just don't dump the res and start from scratch.