Stubborn pH

[Chandara Khan]

Hi Everyone! Now I come to a difficult point and can not find the effective ways to solve it. Before I ask you let me tell you a little bit about my AP. Well, my AP isRaft system which constitutes over 53000 liters of well water. The thing is that my AP has high pH level which is up to 8.2. So far I had used lemon juice as well as vinegar and I noticed that there was a slight drop of pH from 8.2 to 8.0. From my observation, now I see most of my lettuce leaves are yellow or even whiter. To my understanding, I think this high level of pH is leading to the blockage or a disappearance of iron and other important minerals for supporting plant growth. Now my Question to you is “Does any one know how to solve this problem?”  Help!!!

[TCLynx]

You might go get some Muratic Acid, Phosphoric acid, or sulfuric acid to work at counteracting some of the hardness from your well water.  This will probably take many small doses over a couple weeks time.  You do not want to change you pH very drastically all at once since that will likely kill your bacteria, plants and fish.

 

You will want to avoid the lemmon juice since citric acid is antibacterial as is vinegar to a lesser extent.

 

You will want to get some chelated Iron in the mean time to help the veggies out since chelated iron stays more available to the plants even at a higher pH.

 

In the future you will probably want a tank in which you can adjust your water pH before adding the water to your AP system since your well water is probably really hard and adjusting the pH is far safer in a separate tank where you can make the adjustment and then leave it to air for a while before checking the pH and adjusting further if needed.  When doing adjustments directly in the AP system it is very easy to over do it and pH bouncing is worse than the high pH to begin with.

[Chandara Khan]

Thank again and again TCLynx. You are really helpful. Regarding what you’ve mentioned I still have some doubtfulness to ask for further clarification. Your suggestion is to use Muratic Acid, Phosphoric acid, or sulfuric acid to counteract the hardness of my AP system. Can I use acid that is used to refill vehicle batteries? How about diluting? Won’t it be diluted or weaken by AP water? Now I have another idea of replacing 70% or 100% of total water with tap water which costs me around 15$ for 53 cubic meters. It seems replacing water is safer or better than. What do you think?  Iron chelate is not available here. Have you got any alternatives in order to level up iron in my AP? 

[TCLynx]

I'm not sure about batter acid, I just don't know enough to answer that question.

 

Well, As to replacing with tap water, you should run some tests on your tap water before spending money to use it on your system.  And when testing tap water for pH you should have it air out perhaps even bubble it for a bit before checking the pH to be sure you get an accurate reading.  And is the tap water treated with anything like chlorine or chloramine?  I know city water around here is often just as high a pH as my well water since it comes from the same aquifer or in some places they actually adjust the tap water pH up so that the chlorine will work better and so that the water will cause less corrosion in the pipes.

 

Now if you run tests on the tap water and if it has a pH (after airing out) of below 7 and treatment chemicals are not a problem, then you can simply do some partial water changes and then use the tap water for top ups and that will probably go a long way to bringing your pH down without having to change out all your water.

 

I didn't ask before but what are your tanks/raft beds made out of?  Is there anything in your system that could be bringing your pH up?  I know new concrete can have this effect sometimes.

 

If you can't get chelated iron, perhaps you can get Iron sulfate that you can mix with water and use as a foliar feed on the plants.

[Chandara Khan]

Morning TCLynx! 

Yeah, you can say that again. Of course I'll check its pH level first before I make a decision to change some or total of my AP water. How long should i bubble it? Here chlorine is used thus it is not a big deal just to let it stay for a while in my troughs. Well, that's what I have to check whether they are from the same source or not. Like or unlike your case. 

My troughs are made of concrete blocks lined with plastic while my two fish tanks are made of concrete. One of them is old enough and the other is about 6 months old. We have run our system since the 6 months old tank was built. Until now pH is still high.  I know is not a good pH for my plants. I'll find out iron sulfate for my AP.  

 

Have a nice day!

 

TCLynx said:

I'm not sure about batter acid, I just don't know enough to answer that question.

 

Well, As to replacing with tap water, you should run some tests on your tap water before spending money to use it on your system.  And when testing tap water for pH you should have it air out perhaps even bubble it for a bit before checking the pH to be sure you get an accurate reading.  And is the tap water treated with anything like chlorine or chloramine?  I know city water around here is often just as high a pH as my well water since it comes from the same aquifer or in some places they actually adjust the tap water pH up so that the chlorine will work better and so that the water will cause less corrosion in the pipes.

 

Now if you run tests on the tap water and if it has a pH (after airing out) of below 7 and treatment chemicals are not a problem, then you can simply do some partial water changes and then use the tap water for top ups and that will probably go a long way to bringing your pH down without having to change out all your water.

 

I didn't ask before but what are your tanks/raft beds made out of?  Is there anything in your system that could be bringing your pH up?  I know new concrete can have this effect sometimes.

 

If you can't get chelated iron, perhaps you can get Iron sulfate that you can mix with water and use as a foliar feed on the plants.

[TCLynx]

Ya know, a 6 month old concrete fish tank with no coating could be leaching and buffering the pH in your system.  I don't think you want to go to the expense of changing out your water in that case.

 

I believe muratic acid tends to be near the paint, or concrete sections in large hardware stores or departments.

 

But you may really just have to be patient as that fish tank may be affecting your pH for a while.

 

To get the plants doing better you might need to foliar feed quite regularly for a while.  And you might be able to find chelated iron if you search agricultural suppliers, around here I can't find it just at a regular garden center.  There are also special Iron supplements that people sometimes use for planted aquariums but those are costly and not appropriate to an operation the size of yours.

[Chandara Khan]

Yeah, maybe right, TCLynx. I see what you mean. Anyway my well water is at pH  8.2 already though I don't introduce it to the system. Thus what I mean is that I see no significant impact produced by the 6 month old tank.  What do you think? 

 

[TCLynx]

My well water comes in at around 8-8.4 depending on time of year and even so, once the system is cycled, if I'm not adding a lot of top up water the pH will come down naturally.  Even during seasons when I am adding well water for top up regularly the pH of my one system without excessive buffer in it runs around 7.6 with the well water as top up.

 

So, if your system is staying really high pH and you have a fair fish load and have tried adding acid, then I suspect that the tank is doing a fair bit of the buffering.  I don't care how old the concrete is, don't plant acid loving plants next to a concrete driveway or sidewalk or foundation.

 

That said, it could take quite a while for the concrete to stop affecting the pH.  You have a couple choices, one be really patient, find a good source of chelated iron, and use plants that are more tolerant of the higher pH.  Or two, drain the tank and coat it with a food safe coating.  In time the concrete should stop buffering the pH so much but it could take quite a while.

 

As to your high pH top up water.  If you can do the acid adjusting to the top up water before using it in the system that could go a long way to showing if your pH problems are mostly due to the well water or the concrete tanks.  Also, collecting rain water to use as part of your top up water could also help you out to the point that you may start needing to add buffers to the system at some point.

[Larry Reinhardt]

TC is right on - PH bounce is a killer.

 

My water here in central FLorida comes out of the ground at 6.0 PH and has no buffering ability at all. So when I make a serious water change I get PH bounce and the water quickly goes through the roof - off the chart in just a few hours. This is serious stress to the fish and results in belly up the next day. I have to keep Crushed Coral in the filter systems to prevent this from happening. I lost a lot of fish until one day I checked the PH every two hours after adding just 50% new water the change in PH was a real eye opener.