Will this Dosatron do the job?

I suppose it depends on how much water you usually use. Do you have any idea?

 

The reason I ask is that this is rated up to 7 GPM. The comment about smaller home greenhouses is relatively ambiguous. 24x16 isn't very small, though.

Most GH sprinklers have flow ratings. If you take the number of heads and multiply it by the flow rate of each, you'll have a decent idea of how much water you're using per minute.

Personally, I would recommend looking into a Chemilizer. It's about $20 more, and you can have up to 13 GPM (almost twice that of the Dosatron you referenced).

Hope that helps.

 

I think it kind of matters how you water. If you use sprinkler heads, then the GPM will be a factor. On the other hand if you hand water you need to find out what the least amount of pressure it will work on. As far as the ratios go, they are adiquate.

Now then if water pressure is indeed a problem you may want to get a seperate pump to supply your doseatron. Some years ago I changed over to R-O water. Not totally R-O but a 20% mix of city water with 80% R-O water. I have a 90 gallon per day R-O system and I have it set to fill two 55 gallon plastic drums to an 80% mark. Then I fill both barrels up with city water and pump the mixture through my watering system with a seperate electric pump bought from Sears and designed for irrigating systems. Through a system of bypas valves I can regulate the pressure from the pump to a desired pressure setting and I get a good mix of my fertilizer. I know to some it may seem a little bit overboard but it works for me. Our water has a high calcium content and if I use straight city water, it coats the leaves and the walls with a calcium build up that is unsightly. By reducing the city water content, I have very little build up of calcium.

just tom

 

there should be no difference based on pressure with this level of product. They are designed to deliver even amounts of chemicals per measure of water.

The ones that are affected by pressure and stopping and starting is the syphon types.

 

Pressure only becomes an issue if it falls outside of the stated 7-70PSI range.

 

Agreed, and it is likely you will not exceed the flow rate either. A simple way to check is to time the filling of a 5-gallon bucket.

One thing I would recommend is increasing the ratio to 100:1 from the preset 200:1. With some fertilizers, particularly those containing decent levels of calcium and magnesium, precipitation can be an issue.

For example, if you use the MSU RO formula and want 125 ppm N, you need to add 3.55g of fertilizer per gallon of final solution. At 200:1, that's 710 grams (1.56#) per gallon of concentrate, and even though the "practical solubility limit" is 2#/gallon (according to Bill Argo), you're getting close enough that there will be precipitation over time. I have my metering pump set at 100:1, and still keep a submersible pump in the tank, circulating the solution 24/7, just to be sure it's all dissolved.

 

I use two of these they have worked 5 yeares and never missed a beat You have to do some math on your mix


http://www.qcsupply.com/Products/1441.aspx

 

Tom is never overkill its called experiementation