Grow Mediums Time to change your reservoir.

[gone1]

Hey guys,
i found this piece of information about when to change your res.
http://generalhydroponics.com/site/...d_nutrient_management_for_hydroponic_growers/

Every other post or growing guide i read before just stated that you should change your res. once a week.
In that little text GHE recommend that your change your res. once you reach the same volume your reservoir holds via topfeeds.
That mean when i have a tank of 50 liters and my plants drink, lets say 4 liters a day, i need to change my res. every 13 days.
So what do you think about this, is it a good method? And how do you decide when to change your res.

 

[derek420colorado]

You know that is kind of how I do it and never really realized it, but yeah I basically change it once I have gone through all of my intial nutrient solution. So if I put 21 gallons of water in and my babies go through 4 gallons a day I change it about once every 6 or 7 days. I also look for the leaves to tell me when to do it as well, when the leaves start to curl downward and canoe inwards it usually means a salt build up. Good thread max rep for this one for sure!

 

[gone1]

You know that is kind of how I do it and never really realized it, but yeah I basically change it once I have gone through all of my intial nutrient solution. So if I put 21 gallons of water in and my babies go through 4 gallons a day I change it about once every 6 or 7 days. I also look for the leaves to tell me when to do it as well, when the leaves start to curl downward and canoe inwards it usually means a salt build up. Good thread max rep for this one for sure!

Hey Derek, thanks for the rep. and a good tipp with the leaves, i will look out for that!

 

[DWCocha]

Interesting article ! .I kinda follow the method but only later in bloom when it really comes into effect .In the early stages when a small plant doesn't uptake much then I stick to the once a week or maybe 10 days .I feel any longer than that without a res change can cause salt buildup & PH issues ect & would never wait for signs of this before doing something just on the prevention is better than cure basis ! Plus in DWC they need to have EC/PPM increased at regular stages ,quite often the EC/PPM is perfect at the start of the week but dropping severely after a few days ,if left for any time that will make PH swing & start to make the grower go crazy Hop digity

Big 20 gallon resies or RDWC systems would be different ,in that case you would want to get as much growth from each res as possible or your dumping a load of expensive products down the drain ,so can understand why people would follow the method & run there res longer or until the same had been added back .
I only use a 20liter (5gal) buckets so dont waste much with weekly changes .Later on if the plant drinks her 15liters of topping off nutes before the week is up then I change it then like the article says .

Kinda important to mention what the type the hydro system is too ... DWC needs to be kept cleaner & free of any mineral build up more than others ,as there roots are the most sensitive & fully exposed to the nutrient solution at all times, plus they grow at the fastest rate like some battery farm reared animal on steroids lol .Others like NFT / Flood & drain systems can go a bit longer without changes & have buffers like hydrotron ect that can absorb the unused minerals.

"My 2 cents"

 

[gone1]

I have a 60L res. and i dont change it everyweek. I did at the start but i needed so much of my nutrients that i simply didnt want to affort it.
Therefore im glad i found this article and can continue the way i did it.

 

[Groff]

It depends really, on the water volume and nutrient brand. I for one look at the plants, pH and EC swings. I've gone as far as 3 1/2 weeks without a rez change without issues. Its actually becoming more common. Massive savings in nutrients, but I do do RDWC. In regular DWC, nutrients get depleted very fast. in RDWC, the water volume far exceeds DWC, so its more permissive.

I usually let it run 2 weeks easy. At first sign of trouble, I dump the rez.

 

[Grey Bear]

I use a continuous probe to monitor ph,ec,&temp.
I watch the fluctuations (which are normal)
When ph or ec begins to show signs of instability i change the rez.
This can be as long as 12 days or as little as 5 days.
Depending very much on stage of plant and brand of nutrients.