Some good info about ph swings in hydro

[Toleman]

From a pothead site of course but I may give it a go - minus the skunk and RO water. What do you think?

Your PH swings are a huge problem dude.
Heres what you need to do.
Fill your ressy with r.o. water. Adjust the PH of the plain water. Wait 12 hours letting the solution bubble/mix. Then add your nutrients. (You can start feeding this to the plants at this point, if you cant wait). 12 hours after adding the nutrients check PH and adjust one more time if needed. Adjust in small steps. My 40 gallon ressy's only takes about 25ml of ph adjuster each to stabilize it. The key is to allow the ph buffers to do their job before you add in more

Now- how to control your PH...
There are a couple factors that cause your PH to drift. The most common is running the nute solution too strong or too weak. If it's too strong, your PH drops. If it's too weak the PH rises. You have to find the balance point. If you find that the formula above is say, a little strong, and say you have a 20 gallon ressy, mix the nutes for 18 gallons. If it's a little weak, mix it for 22 gallons. You follow?
The other common mistake is mixing your nutrient solution and trying to adjust the PH right away. You have to allow time for the ph buffers in the nutrient solution to do their job. Mix the nutes up, and bubble or circulate for 12 hours before even looking at your PH. You will find the PH to be almost right on target.
I use little or no ph adjusters. (Except during flush).Before I got my RO unit I used tap water, with a starting PPM of 300-400 and a starting PH of 7.4-9.0 (Thats crazy you say! The water is too hard, you will never get stable PH and you will have too much Ca, causing a lockout of Mg!) Bollocks I say.
Every week, on Friday I drain the ressy and fill with plain water. I let that run overnight giving the plants a little flush. This also allows the chlorine and ammonia to evap. On Saturday morning, I mix the nutes into the ressy. I DO NOT adjust ph at this time. Let that run as is overnight. On Sunday morning, I check ph and adjust if needed. Usually don't have to.
Doing things this way has saved me from constant PH drifts, and using about 150 ml of ph down every ressy change, and a little here and there throughout the week to keep it in the desired range. Now, the most I ever have to use is about 25 ml.if any at all. (I have a 40 gallon ressy btw) My Ph stays at a constant 5.5-5.8.

Also forgot to mention your ph can flux strongly depending on your system so its important to get that dialed in along with what your strain likes and can handle..
One thing I will say, Its not good to just keep dumping in chemicals to maintain your ph at 5.8 let it drift as low as 5.2 - 6.0 that way your plants can get everything available to it. When I see my **** fluxuate low then high I know my ladies are absorbing nutrients properly

Chris

 

[LGHT]

I've been into planted tanks for years and still raise very rare and sensitive fresh water shrimp. As a result I know a lot about water and how to balance PH levels. The biggest thing I can stress is GET A GOOD METER. I paid about $200 for my meter, but it's very accurate and also test EC/TDS/TEMP. It has a replaceable electrode cartridge which is good as over time the electrode itself can throw off test. Make sure you also get storage solution for the sensor. The will ensure every test is as accurate as possible. You don't have to spend that much, but a good pH meter alone is around $50-$80.

Once you have a good meter make sure your water is always neutral at 7.0 before you put it into your tank or whatever your putting it into. You can get RO water (water that it's pH level is exactly 7.0) from the store or just get a RO unit for the house. They can be a bit expensive and do waist water, but if your tank is at least 10 gallons it will pay for itself in a couple of years and you can use it for drinking water also.

Last, but not least if and when you think you need to adjust your pH do it very slowly and make sure you allow a day before making any additional changes. The biggest problem with changing pH levels in the water is the build of of TDS (total dissolved solids) over time that will really make your system go crazy. That's why I got a meter that also measures TDS levels. The more you make chemical changes to your water the more TDS build up occurs and when that happens a total water change is the only thing that can help. In a standard 20 gallon tank I would change 80% of my water every 4 weeks to keep the TDS build up down.

If the solution your using doesn't automatically give you the pH you want try and use organic media to lower the pH naturally like Keta Peat nuggets. I read that peppers do well with a lower pH level and can survive in levels as 5.5 or as high at 7.5, with the optimal being slightly over 6.1.

 

[boutros]

Interesting concept(s) and good post. I'm gonna try it and see what's up.

 

[Toleman]

Thanks for the replies

LGTV - my system is only 20litres (5-6 us gallon) so every time I do a water change its the whole lot.

Is it worth doing the change as he says and give a 12hour or so plain water flush?

Do chillis absorb all the different nutrients best at certain ph's but 6.1 is the ideal for them to get everything?

Finally if the plant can pick and chose which nutrients it wants and when - why do you up the grow and lower the bloom for example? is that so it doesnt run out of one before the other and so not to waste the remaining nutes that would have been left over?

Thanks Chris

 

[LGHT]

I don't think the waiting time is necessary as much as starting with RO water or water that's pH 7.0. I have never used those nutes, but I would assume it contains items to lower the pH automatically, but I may be wrong. If it does contain items to to lower pH on it's on you shouldn't need to add anything extra to lower pH unless you want it lower than the nutes take it to.

As the plant gets bigger it will require more nutes that why after it gets to a certain point you up he ratio of nutes. As far as when you want to focus on bloom is up to you. If you have room to grow out a huge plant before it bloomes than don't switch. However if you only have a small space and want fruit sooner switch sooner.

Plants will take in what they need as they need it depending on what stage of growth it's in. You will waste some nutes, but it's better to have it in the water and let it go to waste instead of not having it in the water and the plant suffer.

I never used any pre-planned dosing methods without using c02 injection at the same time. The addition of c02 is huge to underwater plants and will automatically lower the pH level to the perfect point with just a littl. I plan on eventually running a hydro system, but when I do it will certainly include a c02 injection system.

 

[Toleman]

Right thanks for the info.

The situation im in at the minute is I have just emptied the tank and rinsed (2 hours ago). Added plain tap water as I have no RO filter.
Im planning to do this till morning when I will add the nutrients. Im just concerned about the ph at the minute - started at 7.2 and is now at 7.4. will it be ok for 12 hours?

Ive been getting good results so far with 3/5th strength nutrients using grow ratios. High grow, low bloom and medium amount of micro as sugested on the bottle.

Do you think I should add the nutrients now as my EC meter doesn't arrive till the morning.

Chris

 

[LGHT]

Your guess is good as mine. Using plan old tap water may cause the pH to fluctuate for the next 24 hours and it may not. Since tap water is different in every city and town it's hard to say. If anything I would have treated the tap with Amquel first as this would remove a lot of crap like ammonia, chlorine, nitrates, etc etc that will cause pH swings if allowed to build up. If you have a pet store close by get some if not put the nutes in maybe at a lower dose and adjust in 24 hours as the nutes will help condition the water.

 

[Toleman]

Well - I was getting worried as it kept rising so added my nutes.

I wanted to see if I could get away with using no ph down but I only use 2 - 3 ml for 20 litres (5 - 6 us gallons)so I guess im not going to have any problems. I usually put it down to 6.1 a few hours after nutes and then leave for a few more hours and recheck. It stabilises after the 3rd time of adding 1ml ph down for a week - 10days.
It may go longer but I change the solution after that amount of time.

Maybe just going to stick to how I normally do it.

Hope my meter is good - retail at around £30 - £40 ($45 - $60)
just need to remember to keep the tip clean and calibrate regularly.

So if my nutrients go down do I just add a small amount of the correct ratio of each and check after a few hours?
Then recheck ph?

Im currently doing a water change once a week but i suppose I can leave it longer with this meter - maybe 2?

They are in a shed at the minute under a 250w cfl but will go into the greenhouse soon so I might keep on with the grow till they get BIG. Although they are budding already - 4" tall, 6" wide

This is wednesdays pic

Chris

 

[LGHT]

Using pH down is perfectly fine to use and won't cause any major changes as long as you do frequent water changes at least once a month. Once a week is great and will keep build up down, but you should be able to go at least 2 weeks minimum. However I wouldn't add additional pH down until 24 hours after the initial dose so the water has time to completely settle. If you test too soon your pH may still be going down and if you add another dose you may end up adding too much and get your pH too low. RO water will simplify the process, but if you already know your tap water needs to go down a little then your ok. I would still get some amquel to treat that tap no matter what and test your tap every now and then with your meter also. Here in the summer months when water supply decreases the tap water can change daily so I had to get an RO filter. 1 week it's 7.3 and the next it's 8.0!!