What's new
TerraForums Venus Flytrap, Nepenthes, Drosera and more talk

Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

Is 30-40 TDS good enough?

  • Thread starter mcantrell
  • Start date
  • #21
Nate, is yours a permeate pump?.... it should only have isolated the membrane outlet from building up over 5psi back pressure on the membrane.

To be honest, I love mine... efficiencies went way up, water usage went down and prefilter life went way up

They are only useful with systems that use the air tank though... as the air tanks fills with water the back pressure on the membrane outlets goes up and up. This increase in back pressure results in a decrease in pressure differentail across the membrane. This results in a proportional drop in rejection ratio, commonly known as "creep". Also the brine rate goes up proportionally as well, wasting water.

Can you verify what type of pump it is?
It seems like you are referring to a booster pump which is totally different, has a different purpose and would be plumbed totally different.

Permeate pumps do not build up additional pressure, they only isolate

pp100_anlage.gif



Butch
 
  • #22
Nate,

After reading your post again, it seems as though it was hooked up incorrectly and/or faulty. To increase the brine rate it either A) restricted the outlet of the membrane resulting in a reduction in pressure differential or B) restricted the membrane inlet which resulted in a reduction in pressure differential.

Can you verify how it was plumbed into the system please.
Av
 
  • #23
So, I had a thought. If I'm pumping 30 TDS water into my pots, and thus the water in the tray is 30TDS... after said water evaporates and I pour more water in... won't the water in the tray be higher than 30TDS?

In short, do I need to wash out my trays every so often?
 
  • #24
So, I had a thought. If I'm pumping 30 TDS water into my pots, and thus the water in the tray is 30TDS... after said water evaporates and I pour more water in... won't the water in the tray be higher than 30TDS?

In short, do I need to wash out my trays every so often?

Yes.

Basically if your water is 30 tds and then half the water evaporates your tds doubles to 60. etc etc etc every time half the water evaporates the tds doubles. Sooner or later the tds will increase to the point where minerals will begin to precipitate and encrust the trays, bottoms of the pots etc.

If the plants are in contact with the water then it poses potential future problems as the minerals continue to build up. This pretty much goes for anyone that is watering into a closed system where the water can not escape into the ground.
 
  • #25
I imagine it wouldn't have been a problem with the 1-8TDS RO water I was using, but with 30 TDS, something to consider. :)

Also means I might still need to make the occasional trip to the store for the 5 TDS water to flush out pots, especially if I go with a Winebarrel Minibog outside like I want to do...
 
Back
Top