Topping up with nutrients...how to?

[Chris1]

Hey guys. So my plants got a res change, ppm was 100. I topped up with pHd water, which brought my ppm down to about 475.


Today, ppm is down to 400. How do I add water and get the ppm back up? I know plants intake nutrients at different levels, but should I just add a gallon formula back into the res? Something stronger or weaker? :character0029::character0029::character0029:


DWC
76 Temps
65-68 Water Temps
2 Island Sweet Skunk in 20 gallon tote

 

[smokestack23]

I know you say in other threads but I forget where you are in the cycle and how much your system holds.

That said...there are as many different answers as there are members here. Some people say to add plain phd water until you have added 100% of the volume your system holds..others say to add reduced strength nutes... as usual..it all depends.

Here's what I usually do.

I do res changeouts weekly with fresh nutes. Here's an example of one of my systems.
4 site RDWC. System holds 35 gallons. On Fridays I drain and fill with fresh nutes. The 4 plants "drink" about 5 gallons per day in total so I add back 5 gallons of pHed RO water. SOMETIMES, I'll add 5 gal of full strength once throughout the week if PPMs get real low.

The thing that makes me nervous about adding back nutes is that you really have no idea what elements of the nute mixture your plants are using..so..if they're using ..say...100% of the N but only 30% of ..I dunno...something else like Mg, P, K..whatever...you're gonna end up giving them a deficiency or toxicity in some elements.

Of course in a perfect world, your plants will be using equal amounts of the nutes you supply them but that isn't really ever gonna happen unless you can analyze which elements your plants are taking and how much of which they are not. Then you could "design" a diet that exactly meets your strain's requirements.

So..the moral of the story is...you kinda have to play it by ear and see what your plants prefer. Best bet is to keep an accurate log and determine what your strain prefers. Just remember...it's always better and safer..well maybe not ALWAYS..but I prefer to "underfeed" my plants than overfeed. They SEEM to be able to handle lower ppms of a balanced diet better than a nute solution that is too high in ppms. Either is easy to correct in Hydro though.

YMMV, IMHO, FWIW and all those disclaimers.

This is just what I DO with my plants and from what I can tell...they could not be producing faster or better.

 

[hiboy]

I do a rez change once a week. Will add just a and b fertiizer midweek and not the many other added enhancers that i do once a week to get the ppms back up.
hiboy

 

[Mr.Newcastle]

I super mix base nutes and add little by little to the resevoir until my ppms are raised to the number I want, then after mixing for a while, I add my supplements to the resevoir. Havent seen a negative effect from it yet, and hope I don't. Cheers.

 

[Mr.Newcastle]

I super mix base nutes and add little by little to the resevoir until my ppms are raised to the number I want, then after mixing for a while, I add my supplements to the resevoir. Havent seen a negative effect from it yet, and hope I don't. Cheers.

I have not seen too much negative from this method, I would like to say that after reading more into the topic, I have stopped doing this and now go with the PH water top off until the rez change. I didn't find that many farmers doing waht I was doing, and with so many farmers going with the watre as the top off, it made sense to follow suit. And I like it so far. Peace.

 

[hempyftw]

Heh.

I think it also depends on what nutes and system your using. It's a good idea to see what others using a similar set up do.

I only use GH nutes (lucas formula) and they seem to leave very little salt or mineral buildup. This is in an ebb and flow mind you. I've seen others and myself have good success never changing out the nutes. I usually do a swap from veg to bloom nutes in week 1-2 of flower which I do a full empty and fill. After that I just add back 25%-40% of the rez volume with full strength nutes as needed until flush. If I start feeling guilty about not doing much work I do a rez change for shits and giggles/preventative measures.

Might sound crazy but it works for this lazy guy! Plants look happy.

As usual there just isn't one end all answer. Good luck to ya.

 

[WSRidahs]

I've done it both ways in DWC. I use Supernatural nutes and I've noticed that adding the base nutes when topping off to keep ppm up it made a big difference compared to just topping off with plain water. My plants currently drinks 1.25-1.5 gallons per day consistently as long as I add nutes when topping off. When I add only plain water my plants slowly starts to drink less towards the end of the week. Sometimes even less than a gallon.

 

[stillcantroll]

Hey guys. So my plants got a res change, ppm was 100. I topped up with pHd water, which brought my ppm down to about 475.


Today, ppm is down to 400. How do I add water and get the ppm back up? I know plants intake nutrients at different levels, but should I just add a gallon formula back into the res? Something stronger or weaker? :character0029::character0029::character0029:


DWC
76 Temps
65-68 Water Temps
2 Island Sweet Skunk in 20 gallon tote

This really depends on how often you change out your res. I run DWC as well, and I only top off with water, as I change it every week. If you plan on keeping your solution for more than a week, the next step is to look at how your plants are feeding. If your PPM is dropping a little bit, that usually means the plants are up-taking slightly more nutrients than water, or in other words, they are *slightly* underfed... which isn't a bad thing!! And in reality is much better than overfeeding. In a perfect world, you would like your PPM's to be at a concentration that allows your plants to drink nutrients and water at an even rate, so that the only thing that drops is your water level, and your PPM/EC remains steady... unfortunately this takes time to dial in and isn't easy, and varies from strain to strain.

Given what you've mentioned here, I'd recommend mixing a separate smaller reservoir, and going for half-strength of your last change out. Add it back to your desired water level, pH it, and check your ppm, see where you're at, and adjust from there. If you over do it, dilute with water, and go for 1/4th strength next time. if you under-do it, mix them stronger. Good luck dialing that in, nothing beats steady PPM's!!

-SCR

 

[theHERBivore]

stillcantroll.... hit it on the head! Its the most involved in the beginning but when u get it u get it! lucas formula for example...good base to start with but you have to watch out for defficiencies along the way....be able to read your plant. You can add back with a formula on the net...google it but i seriously think that your adding things at a general ratio not know if the plant is taking up that nutrient or not (adventually leading to lock out). Most people fix the lock out by addding more shit and locking out other nutes.

So ne ways the only real for sure way to now what your plants r needing is by watching them...no magical, fill once walk away and have fire formula. :harvest: if your ppms drop when u check it means your plants r hungry and need more nutes... at this time your ph will rise. if youve over feed, your plants will drink more water making your nutes raise and your ph lower. This truely in my opinon is the best way to look at things since different strains require different things... ie: cal/mag etc. etc.

p.s supposidly you can do a lucas 0-5-10 under cfl 0-8-16 under hid no additives added... ph it and either top off regular water til 100% fill back or use a 0-3-6 formula to top off (in flower only i think...not to sure and ive done some research?) and run that til tour ppm's raise above your start level then switch out rez 100%. (lucas only with no additives ...maybe ok for a vacation since ph is supposidly stable and all nutrient requirements are met, but probably not the most efficent as a daily gro and he himself says: that he isnt fimiliar with additives and their negatives or positives since he doesnt use them.) jmo. Do you need all the other additives to harvest a crop...NO -some say those cause the ph drift- ..but somethings also do help since technology and science continue to progress... so even if you do harvest is it the most effective: yield per sq.ft., quality,?, is a discussion thats been going on for years.

This brings up the other question...is a ph drift from say 5.7 to 6.1 the best
( in hydro of course) so that your plant can get the nutrients available at the diff. ph levels... i think so! but with the way that we are reccomending that also means watching your plants for signs and manual ph adjustments up or down depending on nutes being needed at that time before adding more nutes to fix a deficiency! ya dig

hope i didnt drift of subject too much.

 

[St3ve]

I would throw a pump in the rez and pump the water out into a trash can or tub. While its pumping, I add noots to bring it up while its still pumping/mixing. Then after about have of the system is half empty or more I stop and check the PPMs. If I got 400 in the system and I want 500 then I'll mix up the tub to about 550-600 or so and stir it up for a few minutes with the pump. Then just pump it all back into the main system. For me I use a 35g trashcan