Submersible Pump issues!!

Hi all, Ive just recently kicked off my 4 x White Widow ScrOG setup and have just put my clones into their new home (in the process of starting a journal). Im running into a major issue with the watering which i hope someone else has experienced with, im pulling my hair out!

I have a 100L reservoir (which I filled last night) with a fairly small submersible aquarium style pump. It turns on for 1 minute per day for feeding, however when the pump shuts off after 1 minute the water keeps flowing (by vacuum I believe, like when you siphon something). In one feed session last night, it emptied 50L onto my babies!
The 50L mark is around the same level my feed hoses are (top of the pot) so that probably explains why it empties itself to the halfway mark.

It seems strange that my local Hydro shop would sell these pumps if they had lots of people with this problem. I am wondering if maybe I am doing something wrong here such as mounting or maybe I should just buy a better pump? I had it mounted on the side of the tank using the suction cups allowing space for water to flow into through the intake, I also mounted it on the bottom and still having the same issue.

Any ideas would be VERY muchly appreciated!

Your problem is Gravity. I learned this some time ago as well. The 50L of water that sits on top of the pump is creating pressure pushing the rest of the water through the pump. You will notice that the vacuum effect applies here as well. Your problem is simply that when the water runs, the hoses are still full of water and gravity as well as vacuum are forcing the remaining water into the area where your plants are. A simple fix is only putting as much water as you need, running the rez dry and then draining. Otherwise you are going to be stuck with this problem quite some time. I:n all the pump isn't the problem, it is your setup.

1 minute a day? Dead plants soon if ghat is not a typo, and if you show me a pic of your system I can help out, but reading what you wrote I have not a clue

Didn't see the above response, but he is right about it not being the pump, it is the way you are set up that is your problem

Thanks for the responses guys, I had a feeling it would be something to do with the setup. I guess anything over the 50L mark is wasted coz everytime the pump kicks in it will keep draining (damn gravity!). It would be nice to have a floating pump...

LOSTCOASTLOCAL - 1 minute/day - as per advice given from my local hydro shop. Im running a Drain to Waste system with coco and was advised to begin with 1minute/day and then gradually step it up. Is this too much/little?? This is my first time with this new watering system, I used to run autopots so have a bit of a learning curve ahead of me!

just found this info:

Overview:

Been using a top drip system and building a few for fellow patients. The can be hooked up to a pump and you can switch it on and off to water all your plants at once. (or use a timer)

Please note: If you use a tall res (meaning the water line is higher than the trays a.k.a column or barrel type) and a timer or manually turn on/off by hand. You will need to either unhook your water line (after each time you feed) or install a back flow valve to prevent siphoning.

Click to expand...

Hope this helps anyone else with tall barrel-type reservoirs!

Your Rez water height must be lower than you drippers.

Gravity may be your starting problem but once the pump gets the solution flowing it will create a vacum until the water level is equal to where your drippers are located

Yep, thats definitely it, the res water level is equal to the dripper height now (after emptying around 50L in one feed). I have a very low room (hence ScrOG) so will probably need to incorporate a second longer, flatter trough, move the submersible pump to that and add a float valve - filled by the barrell I already have... any other ideas would be appreciated! Thanks for the comments so far, i feel enlightened now!

...aah the fun of trying new systems!