PH is on the constant rise, and FAST? Dont know why.

[MMRC Grower]

I've read up on this and I just cant find a solution.

So here's my issue. Every time I lower my PH, it goes right back up within a day. For instance... the other day I dropped my PH down to 5.2 at night before bed. I woke up in the morning and I was already at 5.8. Today I dropped it to 5.4 at 2pm. 6 hours later at 8pm I was at 5.6.

Its a constant battle to keep my PH down and I cant figure out why. If left unattended for a entire day without adding PH down, I'll be well over 6.0 and on my way to nute lockout.

If anyone can help, that would be great. Here's my info....

I'm currently using a 6 bucket, Ebb and Flow system. RO water with around 1,000 ppm after nutes. My plants are about a foot tall and a foot and a half away from a 1,000 watt MH light, with an air cooled reflector. Growing in Hydrotron rocks on a 4 times per day, 45 minute flood and drain cycle. Lights are on 18/6. 20 Gallon, clear plastic res/tote. I have two air stones sitting in my res that only come on when the pump is on. I just turned them back on this afternoon to run 24/7 to get more oxygen in the water/nutes. My room temperatures stay between 65-75 degrees. Constant air movement with osilating fan and 780 cfm exhaust fan. My nutes are 3 part GH, with Floralicious Plus, FloraBlend and CalMag Plus. My RO water starts out at about 11 ppm.

Any suggestions, or good ways to help stabilize my PH would be appreciated.

 

[onthe420train]

Re: PH is on the constant rise, and FAST? Dont know why...

you must run pHed water through your medium until your runoff is where you want it to be : ) also during aggressive growth your plants will eat nutrients at different rates calling for a quicker pH adjustment as the ratios of chemicals and buffers change.

 

[MMRC Grower]

Re: PH is on the constant rise, and FAST? Dont know why...

you must run pHed water through your medium until your runoff is where you want it to be : ) also during aggressive growth your plants will eat nutrients at different rates calling for a quicker pH adjustment as the ratios of chemicals and buffers change.

I grow hydroponics. My medium is whatever PH my nute water is. Runoff is usually a term used when growing in soil.

I understand that plants consume nutrients at different levels depending on there growth stage, but my PPM is staying around the same level each day. I also understand that nutrients have PH buffers and that they do change over time, and if left for too long they can become very unstable, but this happens to me the same day I change my entire res out with fresh nutes and RO water. And it continues to change from that point on.

My plants are really beginning to consume a lot of water. I had to add back 4 gallons yesterday because I skipped the day before. So 4 gallons in 2 days between only 6 plants.

So I'm going to shoot for a bigger reservoir and see what happens with that. I'll go with a 40 gallon instead of my 20. This should allow me to not have to do daily PH adjustments.

Thanks for you help.

 

[onthe420train]

Re: PH is on the constant rise, and FAST? Dont know why...

even in hydro lots of mediums will fluctuate pH bro - I'm not tellin you whats what just tryin to help don't take it personally =P not implying you don't know these things but if you didn't rinse your hydroton that could well likely be your problem.

sounds like ur on top of it though res size could definitely be the issue - they'll drink over a gallon a day a plant when they are big and thirsty

 

[MMRC Grower]

Re: PH is on the constant rise, and FAST? Dont know why...

even in hydro lots of mediums will fluctuate pH bro - I'm not tellin you whats what just tryin to help don't take it personally =P not implying you don't know these things but if you didn't rinse your hydroton that could well likely be your problem.

sounds like ur on top of it though res size could definitely be the issue - they'll drink over a gallon a day a plant when they are big and thirsty

I must have came off with the wrong tone. I wasnt taking it personal or offensive. I didnt mean to make it sound that way either. I was trying to throw out there what I knew and have kinda ruled out as possible causes. Thats it.

The hydrotron is pretty new. I've only had it in the system for 2-3 weeks now, but I did rinse it. There was still a little powder left over on my first res fill, but since then I've flushed and changed nutes 2-3 times.

So the only thing I can think of now is the res size. I've heard that 3-5 gallons per plants is the minimum that you want to be at and I'm barely there with 20 gallons. So I'll double it and see what happens. If it still continues, I'll have to find a new water source and go from there.

 

[TheAnswer1776]

Re: PH is on the constant rise, and FAST? Dont know why...

I must have came off with the wrong tone. I wasnt taking it personal or offensive. I didnt mean to make it sound that way either. I was trying to throw out there what I knew and have kinda ruled out as possible causes. Thats it.

The hydrotron is pretty new. I've only had it in the system for 2-3 weeks now, but I did rinse it. There was still a little powder left over on my first res fill, but since then I've flushed and changed nutes 2-3 times.

So the only thing I can think of now is the res size. I've heard that 3-5 gallons per plants is the minimum that you want to be at and I'm barely there with 20 gallons. So I'll double it and see what happens. If it still continues, I'll have to find a new water source and go from there.

The res size is fine! Doubling the size will only cost you more in nutes. If your plants are drinking that much water daily then I think the PH fluctuation might be normal due to the plants feeding on nutes and water. In the grows I have done in the past PH fluctuations from 5.8 to 6.3 in 24 hours was pretty normal and actually aids the plants in uptaking the different nutrients that become available at different PH levels. Also with a flood and drain you will get slightly different readings after the system circulates. I reccomend daily PH checks, but if you can't check it that often you could always use a PH buffer like for an aquarium. People have great success with them. Hope this helps!

 

[MMRC Grower]

Re: PH is on the constant rise, and FAST? Dont know why...

The res size is fine! Doubling the size will only cost you more in nutes. If your plants are drinking that much water daily then I think the PH fluctuation might be normal due to the plants feeding on nutes and water. In the grows I have done in the past PH fluctuations from 5.8 to 6.3 in 24 hours was pretty normal and actually aids the plants in uptaking the different nutrients that become available at different PH levels. Also with a flood and drain you will get slightly different readings after the system circulates. I reccomend daily PH checks, but if you can't check it that often you could always use a PH buffer like for an aquarium. People have great success with them. Hope this helps!

PH buffers for Aquariums.... Excellent advice!! I am able to check it every day, and I know the fluctuation is good, but I want to stabilize it just a little. Just to the point where I dont have to go in there and add PH down every single day. Every other day would be fine.

Very true on the bigger res costing more money, but right now the entire res empties itself, leaving only about a gallon in the bottom just to fill all the buckets. So if I dont add water to it every day, then the bucket dont get filled up all the way. So instead of 40 gallons, I'll probably shoot for 25-30, just so I can have a little less daily maintenance.

I'm definitely going to look into the aquarium PH buffers. Thanks a lot for the help!!

 

[Retired One]

20 Gallon, clear plastic res/tote.

Algea...paint, wrap or otherwise lightproof your res. Algea can cause serious PH problems before it's even visable. Treat your res with algeacide and get the light out of it and I'm sure things will improve. On the subject of aquarium PH buffers...not the best idea. The natural tendancy will be for your PH to go down over time, this is good because different nutes absorb best at different PH levels, so locking down your PH can actually hurt your grow.

Lightproof your res and treat it with algeacide, and I'll bet things get better.

 

[MMRC Grower]

Algea...paint, wrap or otherwise lightproof your res. Algea can cause serious PH problems before it's even visable. Treat your res with algeacide and get the light out of it and I'm sure things will improve. On the subject of aquarium PH buffers...not the best idea. The natural tendancy will be for your PH to go down over time, this is good because different nutes absorb best at different PH levels, so locking down your PH can actually hurt your grow.

Lightproof your res and treat it with algeacide, and I'll bet things get better.

Hmmmm..... So there could be algae even if I cant see it?? Interesting. I'll do that first then.

Thanks a lot. I really appreciate every ones help.

 

[MMRC Grower]

Question: Does Hydrogen Peroxide help fight Algae??

 

[Tyrone Hamilton]

Question: Does Hydrogen Peroxide help fight Algae??

Maybe, but you can buy algaecide at any pet store or walmart.

 

[onthe420train]

If your observations are that the algae is not affecting the plants there is no need to get rid of it. However, some gardeners and most hydroponic enthusiasts think it can be a problem.

One way to get rid of algae is to deprive it of light, which it needs to photosynthesize. The method is very safe because it involves no chemicals. You can affix black polyethylene plastic collars around the plant stems that cover the tops of the rockwool cubes. Other materials that can be used are white cardboard or styrofoam. If collars are inconvenient, then strips can be placed over the line of cubes to cover them.

Hydrogen peroxide can be added to the water and will deter growth of algae, but it may also affect fertilizer chemistry.

Ed is the man

 

[MMRC Grower]

Ed is the man

Thanks for the info.

 

[HomeGrownHairy]

Question: Does Hydrogen Peroxide help fight Algae??

Yers. it will kill it. I use SM-90 in my tank the entire grow and it has kept away all the bad stuff.

 

[Krack420]

If you don't see any green algae, then you probably don't have an algae problem. Mr. 1776 and 420Train have the right idea. Fluctuation is normal with a hydro setup. Think about it this way. Nutes lower your PH in your res. As your plants eat more nutes, the PH will rise. To alleviate the problem, you can get a bigger res size which will buffer the change a little, but 1776 is right about it costing you more in nutes when you do res changes. If you can stay on top of things and not leave your plants for a prolonged period of time, then you can stay with the same res size.

 

[MMRC Grower]

If you don't see any green algae, then you probably don't have an algae problem. Mr. 1776 and 420Train have the right idea. Fluctuation is normal with a hydro setup. Think about it this way. Nutes lower your PH in your res. As your plants eat more nutes, the PH will rise. To alleviate the problem, you can get a bigger res size which will buffer the change a little, but 1776 is right about it costing you more in nutes when you do res changes. If you can stay on top of things and not leave your plants for a prolonged period of time, then you can stay with the same res size.

Thanks a lot. Well, I spray painted my res black. I put enough coats so that light couldnt get through. So that will eliminate the light/algae possibility. I mixed half tap water in with the res change that I did the other day. So my starting ppm was around 100. Not too bad. I'm hoping that the tap water will stabilize the ph just a little. Well see what happens. I'm posting some pics today on my grow journal if anyone wants to check them out.

 

[spyvy]

Had the same problem started with algae with light getting in.. Then I had the ph going up and down daily. Just with seedlings turned out it was the city water they use Cloramate it is like a buffer. I would set my ph at 8pm to 5.8 then check in the morning it would be like 6.2.. .
So now I mix 2 heaping tablespoons to 8 gallons of water & 1 tablespoon for 3 1/2 gallons of water in my dwc of bakeing soda to the water then ph balance it out .
It takes more ph down but the ph stays stable for days now . Even with plants eating it only goes a little way like from 5.7. to 5.88. works great to stabilize the ph .. The fish tank stuff I think has some bad stuff in it for human consumption , Would stay away from that ..good luck

 

[MMRC Grower]

Had the same problem started with algae with light getting in.. Then I had the ph going up and down daily. Just with seedlings turned out it was the city water they use Cloramate it is like a buffer. I would set my ph at 8pm to 5.8 then check in the morning it would be like 6.2.. .
So now I mix 2 heaping tablespoons to 8 gallons of water & 1 tablespoon for 3 1/2 gallons of water in my dwc of bakeing soda to the water then ph balance it out .
It takes more ph down but the ph stays stable for days now . Even with plants eating it only goes a little way like from 5.7. to 5.88. works great to stabilize the ph .. The fish tank stuff I think has some bad stuff in it for human consumption , Would stay away from that ..good luck

So you use baking soda as a PH buffer?

 

[HomeGrownHairy]

Had the same problem started with algae with light getting in.. Then I had the ph going up and down daily. Just with seedlings turned out it was the city water they use Cloramate it is like a buffer. I would set my ph at 8pm to 5.8 then check in the morning it would be like 6.2.. .
So now I mix 2 heaping tablespoons to 8 gallons of water & 1 tablespoon for 3 1/2 gallons of water in my dwc of bakeing soda to the water then ph balance it out .
It takes more ph down but the ph stays stable for days now . Even with plants eating it only goes a little way like from 5.7. to 5.88. works great to stabilize the ph .. The fish tank stuff I think has some bad stuff in it for human consumption , Would stay away from that ..good luck

You use baking soda, really? Never used that. How is it beneficial to your plants?

 

[HomeGrownHairy]

The pH fixes for aquariums will work just fine in hydro. Where did you here that? It doesn't hurt the fish so it wouldn't cause any problems to stoners either.