Hi all! FNG first time DWC - Please take a look and give opinions!

[TWINTURBODOGO]

Our setup is top fed dwc with 185w LED. Single quarkle strain in 4th week of flower in 2'x4'x5' tent, temp is set to 68-75. Dual outlet air pump for 60g aquarium with 2 10" stones.
6gal res with 3gal r/o water.
Recently switched to tigerbloom from age old bloom organic.
2tsp per gal nuts, working up to 1 tsp per gal.
1tsp per gal of hydroguard and cal/mag.
530 ppm
ph 5.5-6.5 most of the time

We had some root issues from what I think was to little o2. Had 2 small aquarium stones on small pump switched to bigger pump, bigger stones, peroxide root bath at last water change. Now have new root growth and no more weird deficiency signs (fingers crossed)!

But now we're having some ph down swing issues. Ph at water change 5.8ish by morning of day two 4.5 bumped back to 5.0 this morning day four 4.0.
Have heard ph down in flower is common but this much of a swing?

Sorry for the long windedness of it all! Any thoughts are welcome thanks!

 

[iwltfum]

Tigerbloom will definitely lower your pH and if you aren't using an effective alkalinity increaser, it will drop more quickly. How often are you completely draining your res and replacing the water?

 

[TWINTURBODOGO]

Oh really I didn't know that before hand, why does it lower ph?
We use GH ph up or down and do a water change every 7 days.

 

[iwltfum]

Oh really I didn't know that before hand, why does it lower ph?
We use GH ph up or down and do a water change every 7 days.

The short of why tiger bloom is acidic is because many of the ingredients contain ethylenediaminetetraacetic acid (EDTA) - a polyprotic acid, which means that each molecule has more than one ionizable H+. The EDTA in the metals makes them act as acidic buffering agents that keep the pH low. The time it takes for the molecules to ionize is between several hours and several days, which is why it keeps on bringing your pH down over several days time.

From what I hear, GH up and down are pretty weak when it comes to long term pH stability. I don't grow hydroponically anymore, so I haven't had to look into what a good alternative alkalinity increaser might be. I would try something from a pool shop maybe (like hot tub alkalinity increaser) it should just be pure sodium carbonate.

Unfortunately, it's a possibility you will need to check (and maybe adjust) your pH daily even if you use a better long term alkalinity increaser just because of the nature of the tiger bloom.

 

[Papageno]

I use Mad Farmers Silica for an UP. Most all silica products are very alkaline and can be used as an up instead.

I sounds like you are trying to run sterile and I don't do that. Your drop sounds much faster than normal Blooming drop from nute profile switch over. how long have you been in bloom? how big is the res? If it is a multi-plant res what is the gallons per plant? How often are you topping off?

If you are just dumping it once a week and not topping off in between and letting it drop down that would be your problem. The dumping once a week (which I avoid) has nothing to do with the water level being at the proper height. Also the height isn't really the issue. you never want the gallons per plant to go below about 5 gallons per plant. You can and it will work it just gets harder. At 2 gallons per plant it is very very hard to keep the pH stable.

I run a 35 gallon tote at between 25-30 gallons. In heavy growth times I can be dumping in a 5 gallon bucket each day of top off running 4 plants. That is heavy growth usually it is less but still if you don't budget for the heaviest times it gets difficult.

 

[TWINTURBODOGO]

Thanks for the responses, and thank you for the lesson on why tigerbloom acts the way it does.

I do top off when water gets low, with either nuts or just ph plain r/o water depending on the ppm reading.
Res is a 6g tote with 3g water.
Single plant 4th week of bloom.

Yes we try to keep it as sterile as possible. Thought that was the way to do it lol.

 

[Papageno]

Well keeping it sterile is one thing...that is totally something different.

You must keep it sterile. But most people run with beneficial bacteria as it aids in better healthier faster growing plants. Most companies sell this stuff and recommend it. Most experienced growers recommend it. Most people not doing it eventually get a Pythium infection they can not stop without beneficial bacteria.

So that is what I am talking about. You either run a living res or you constantly dump in a bunch of expensive chemicals to keep it all sterile. It is a religious debate and many people will argue about this forever. Both work you just have to choose one and go with it.

The biggest problem is not know about this. People who don't understand this either try dumping in beneficial stuff into a sterile situation flushing money down the drain or run a sterile system properly and don't understand why or even worse they are doing neither and just brewing up a situation where a massive infection will bring down the crop.

It is hard to tell from your description if you are using the H2O2 in the res regular enough and to the right concentration to prevent pithyum.

Here is some light reading. Either way works but if you don't choose a side and do it full force you will have a problem. These problems can start with uncontrollable pH. My pH is stable and needs no adjustment and I run a res well longer than 4 weeks. I try to change before bloom when I am changing over the nute profile and at flush when I want to remove all nutes. My buddy goes the entire grow without changing the res.

What's the difference between a sterile rez and a beneficial rez?

 

[TWINTURBODOGO]

O ok I see what you ment now. We have been using hydroguard from the beginning. And dose according to instructions.
When we suspected root o2 issues we let plants roots sit in H202 ph'd water while cleaning/sterilizing res. Rinsed roots in ph'd water before going back into res.
Now see new root growth this week and no new signs of of problems.

 

[TWINTURBODOGO]

Well this morning ph was back down to 4.0 ish. I think the plan is to go up to 4 gal in res and look at another type of nuts.
Is it a good idea to flush and change nuts at this stage or should we just adjust every day and continue tigerbloom?

Any recommendations on nutrients?

 

[Papageno]

Well it is hard becasue we still don't know what your setup is. When you say

plan is to go up to 4 gal

that implies you are running at less than 4 gallons. Well considering that you should be running not less than 5 gallons a plant I can't say I understand what you are doing so I can't really help. What you are describing is usually either a mass infection which would require a strong does of a home brewed microbial tea or a massive dosing for a long time of some serious H2O2 (not the stuff from the pharmacy, that is too weak) or you are running the res too low and need to up your res size.

6gal res with 3gal r/o water.

So does that mean you are running at 3 gallons a plant? Most people can't maintain that.


Pictures work great if you don't want to explain your setup.

Top feed DWC should have the top feed shut off once the roots hit the res otherwise you risk an infection that will cause this. It is not meant to be on after the roots hit the res.

Specs on the air pump would be useful. What is needed for an aquarium is not the same as DWC and most people use a LOT more than most aquarium pumps. But it all comes down to how the water is moving and how big the res is.

If you are growing in single site unlinked "buckets" you need a bigger air stone then if the solution is moving through an external res picking up air from turbulence along the way.

It sounds like your system is undersized both in res and air-stones and also running a top drip not letting the roots in the medium dry out. That is a triple combo setting up for an infection.

 

[TWINTURBODOGO]

Sorry if I was unclear bout our setup in the first post.
We have a single plant in a 6g tote using 3g of water that will be bumped up to 4 now.

 

[TWINTURBODOGO]

We are using the tote of this size because it is shorter then a 5g bucket and has 1 more gallon.
We wanted short to leave as much room for the light, we only have 5' high to work with.
Is a 6g resivour to small for a single plant?

 

[Papageno]

No 4 is dealt with just fine you just need to monitor and top frequently.

I don't know how optimal all the conditions are but I will need more than a gallon a plant in strong veg per day. You probably wont get there but you will need to be topping it off regularly. I feel like 4 is the absolute min. By that I mean I might let it get to 4 before topping off. At 3 you are starting to have issues and 2 is uncontrollable. So if you are starting at 4 you are going to be topping off constantly.

If you have more space on the ground you can add a second res that you attach via bulk head connectors and run the pump in the secondary res to both to get circulation and more volume.

People run at 4 all the time and they are fine. It comes down to how much labor you want to put into it.

For example when I described mine it was at 30 gallons with my level just bellow the net pots. So for 4 plants I can let it go through 10 gallons of water before I "must" be concerned and consider getting out there. Now honestly after 5 gallons I start to get worried about the balance of things and like to top off to get the PPM's correct. In a healthy res the PPM's determine the pH. It is a complicated dance with the roots and I don't have time to explain it but it is why when you switch to bloom nutes the pH drops for a while and it is why normally (in a healthy res) if the pH is slowly dropping, you need to up the nutes.

If you want to know about how to run DWC I helped a guy recently through his whole grow. I will paste a link to his journal which is a fine read. He documented everything very well proving out all sorts of science many people do not understand nor believe about hydro. Give it a read through and you will learn a lot. My setup is similar to his only I have the next size up tub. If you notice the tub does not have a flat top. It has a raised top allowing me to get more solution in the res while keeping the baskets out of the solution.


ClosetCase420's - RDWC - 600W MH/HPS - Wonder Woman - Grow Journal - 2015

 

[TWINTURBODOGO]

Wow VI thank you, that was a good read and lots of great info documented very well. I have a lot clearer idea of how ppm's and ph work. Sadly I can't say I an that organized lol.
And yes we've fought with ph fluctuations since the beginning. Hope increasing the water in our res will make it easier to manage.
I have some pics I took the other day, will load em in a bit.

I think we're still battling root rot. All was fine for a few days after water change, resivour and equipment cleaning. But plant is now looking sad again and res is starting to smell slightly again.

We have been using hydroguard from the beginning. But only dose according to instructions. To fight off the bad bacteria should we be dosing more or using something different all together to clear this up, with good bacteria?

 

[TWINTURBODOGO]

Also we are looking at a new air pump and stones. Right now we have a 20-60g walfart special pump and two 10" long stones also from walfart.
We pulled the water pump hose out of the pot and are now using it just to circulate the resivour water too.

 

[TWINTURBODOGO]

Here are a few pics of the plant.

 

[Papageno]

By the way you have too much nitrogen in there. Excess nutes help aid in bad bacteria growing that can cause root rot and other things. But eitherway there are multiple signs there of too much nitrogen. It would be wise to back off a bit I think.

 

[TWINTURBODOGO]

Thank you VI, we're doin a water change today and I will document my numbers and follow them closely for the next few days and post everything as we go.
Could the low ph problems be a cause of the clawing and cupping of the leafs?

 

[TWINTURBODOGO]

So since upping the resivour water to 4g, the ph has held a lot more stable then before.

But the ppm over the last 3 days has climbed 432 one day next day 440 this morning 460.

So the plant is drinking but not taking up nuts, right? Partly due to the ph being low?

We have new water ready, started with 4g r/o water 8 ppm.
Added 10ml tigerbloom, 20ml cal/mag, 20ml hydroguard.
Ph'd to 6.0 (just have drops for ph testing now) ppm is 456.

We dosed the cal/mag according to instructions but should we have lowered that dose to help bring down nitrogen?

 

[Papageno]

Clawing, the too deep a green, the leaf tips drooping are all signs of toxic levels of nitrogen. It can cause stunting and other problems.

So you are fine just don't go any higher. That plant is closer to 350-400ppm range. Especially with the reduced lighting. Your lights are fine for growing just not optimal. Optimal is a relative thing. If you can handle a 600W HID or equivalent then you can run higher nutes as there is more photosynthesis. Since you are running much lower you will want less nutes.


Look into a product called MOAB. It has no nitrogen and has high levels of Phos and Potassium. Good for your situation where you need to back up the nitrogen a bit without backing off on the bloom nutes.

Now that you have some stability thins will be easier. the roots may need a bit of time to adjust but you will be fine. In general it is better to run the nutes lighter then to run high and deal with burn or worse growth inhibiting levels of nitrogen.

By the way over dosing nitrogen is the number 1 most common problem and it is not catastrophic. Just be cool the rest of the grow.