Water pH and Peat Moss

[timvz]

Yesterday a trusted pond plants vendor suggested I use Peat Moss to try and lower my pH. It isn't terribly high (8.2), but I believe it may be what causes my water hyacinth to die. Does anyone have any recommendations for using Peat Moss for this purpose? Thanks.

 

[addy1]

At 8.2 I would leave it alone. What was the ph after you put in the peat moss. I use it for my acidic loving plants.

 

[timvz]

I haven't done anything to it yet. Just researching right now. Mainly I'm looking for reasons that the hyacinth is dying. I don't know for sure that it's the pH, I guess. Could be too much sun, or dry desert air I suppose. The plants guy thought it could be that the relatively high pH was inhibiting certain bacteria that benefit the hyacinth.

 

[Priscilla]

My PH is 7.5 and I'm not having luck with the water hyacinth either. I buy it from a place here, its in full sun, they are so happy there they are even growing out of the pond on dry ground. However, I buy them, in two weeks they start to yellow and it goes down hill from there. This batch is the longest they have latest. I have them in floating net baskets. So they still look pretty good, but I've only had two flower. I think the fish are nibbling them.

I don't know what my salt levels are, but they have told me at the plant store that their salt levels are high. Not sure if that's what is making a difference.

 

[pecan]

Interesting. I thought peat moss was only used to clear green water. How much is it supposed to change your ph?

Never mind I was thinking barely.

 

[crsublette]

1) Yesterday a trusted pond plants vendor suggested I use Peat Moss to try and lower my pH. It isn't terribly high (8.2), but 2) I believe it may be what causes my water hyacinth to die. 1) Does anyone have any recommendations for using Peat Moss for this purpose? Thanks.

1) Yesterday a trusted pond plants vendor suggested I use Peat Moss to try and lower my pH. It isn't terribly high (8.2)... Does anyone have any recommendations for using Peat Moss for this purpose?

A stable pH is far more healthy for you instead of aiming for a specific lower pH. This is due to how pH changes can reduce fish's immune system, dependent on the fish species.

A stable pH of 8.2 is quite fine, that is assuming your alkalinity is correct. You can have a 8.2 pH and be in bad shape, that is if the pH is 7.3 in the morning and 8.2 in the evening. Ultimately, this fluctuation is due to alkalinity concentration. To learn more, then, amongst the other threads in this Chemistry sub-forum that you should read, check out pH & KH -- Questions (and a Good Article)

Peat Moss can lower your pH only if your alkalinity is not terribly high, as described in the aforementioned thread. Alkalinity is the measurement of resistance capability for water's pH to be lowered by other "stuff". If you have low alkalinity, then there is a greater success for Peat Moss to lower your pH. However, if your alkalinity is higher, once the pH lowers, then the water's pH will rubber band back up to where it was again.

Now, Peat Moss can effectively lower the pH in localized areas, even in high alkalinity situations, such as around plant roots, but, when talking about a body of water, then the only good way to lower your pH is by lowering your water's KH through various other methods, which is expensive and kind of complicated through the involvement of chemical dilution using various other products.

If your alkalinity is low enough, then you can effectively use Peat Moss to lower the pH, but you will have to use a high quantity of it and constantly refresh it by placing in new Peat Moss. It is easier using Peat Moss to lower the pH in a small aquarium situation rather than in a pond situation.

Again, a stable pH is far more healthy for you instead of aiming for a specific lower pH. This is due to how pH changes can reduce fish's immune system, dependent on the fish species or you know how to manage the alkalinity.



2) I believe it may be what causes my water hyacinth to die.

This can be due to several reasons...

A) Fish eating the roots. This can be solved by installing the hyacinth in a DIY'd floating plant ring, as described in this thread.

B) There are particular blue-green string algae species that actually emit chemicals that inhibit Water Hyacinth growth, by forcing the plant from receiving iron, which can eventually kill the plant. So, use some elbow grease and a toilet brush to gently scrub the string algae off or use some other techniques.

C) Iron deficiency. Iron is an important secondary macro-nutrient for plants. When the plant is yellowish or chlorosis, then this can possibly mean an iron deficiency, but this is not always, except it is much of the time with Water Hyacinth. However, in an aquatic environment, not much different than other compounds, iron exists in two states dependent on the water's pH. In high pH water, then more of the iron is in the formation of Ferric Iron (Fe+++), which is plant insoluble. In low pH water, then more of the iron is in the formation of Ferrous Iron (Fe++), which is plant soluble.

Plant's response to this is for them to create their own "chelating" agents, called phytosiderophores, to convert iron into ferrous iron and plant roots also create a localized acidic zone, that is lower the pH, around the plants roots so to make iron more soluble. "Chelating" agents helps to digest and dissolve the compound into the more soluble counterpart. There are various plants known to excrete higher concentrations of the natural iron chelating compound, involving phytosiderophores, that can be grown in tandem with other plants; Barley, rye, and other grasses are good companion plants to help improve the solubility of iron in high pH waters. Also, as plants use a cation exchange system to make nutrients soluble, the plants excrete hydrogen cation's (H+) in order to create a localize acidic zone so to make the nutrients more soluble. However, both of these solutions requires the plants to be anchored in a medium such as gravel or soil or sand or etc... When the plant is freely floating, then these solutions do not apply. So, the only other option is to do one of two things: 1) lower the entire water body's pH ; 2) add a product in your water to help make iron more plant soluble.

As mentioned in my response to point #1, lower the pH of the entire water body involves chemical dilution, that is essentially replacing the current body of water with "something else" or convert the current water into "something else". This "something else" can be rain water or deionized reverse osmosis water. Also, with a cheaper and more dangerous method if done incorrectly, then acid can be used to convert the water into "something else" with a lower pH, that is by "burning off" the alkalinity. However, these approaches can be expensive if your source water is very alkaline or can be more dangerous if proper attention is not paid.

The cheapest solution might be to dose your pond water with a particular product that increases the availability of iron. Now, even though your pH is high at 8.2, there is still a noticeable amount of iron that is plant soluble. However, there is just "not enough" iron that is plant soluble. So, by increasing the overall iron concentration, then you also increase the solubility of iron for the plants. However, this can be expensive due to how much iron you might have to add to the water. The possibly cheaper option is to dose the water with a iron that comes with its own chelating agent, which there are many forms of this and one most common form is toxic that you do not want to use.

There are three forms of chelated iron products: 1) FeEDTA ; 2) FeDTPA ; 3) FeEDDHA. Do NOT use FeEDTA. EDTA is a good chelating agent in other areas and is only effective in water with a pH of 6.3 or lower, but, in our pond context and at concentrations we will use, the EDTA can become quite toxic and actually can act as a herbicide. Unfortunately, FeEDTA is the most commonly sold from hydroponic, aquatic, and aqua-ponic stores; stay away from it EDTA!

The two best iron chelated products to use for our ponds are FeDTPA and FeEDDHA. FeDTPA can be commonly found from a local hardware store and, even though it is expensive, it is quite concentrated and a 5 pound bag of it lasts for a very long time for even systems or ponds that are 10,000 gallons. However, the disadvantage of FeDTPA is it becomes inactive when the water's pH goes above 7.5, but this product is very easy to find.

The absolute best iron product with a chelating agent is FeEDDHA. The reason why it is so good is due to the fact it only becomes inactive if the water's pH is above 9.0, which a pH above 9.0 should never happen for anyone caring for fish and plants. Unfortunately, this product can be tough to find, which means this product can be expensive and may likely have to be ordered from the internet.

Last option is to apply iron as a foliar spray on the plant by purchasing Ferrous Sulfate, mix it in water, and spray directly on the plant in the early mornings or late evenings.

Unfortunately, UV device usage can cause iron to precipitate, that is make it plant insoluble. However, this does not precipitate all of the iron. This just means the iron dosage will need to be increased, as described why previously.

Also, feeding the fish with a high iron fish feed such as vegetables or other feed with high iron will not work well since the fish's digestion actually oxidizes most of the iron. Also, adding rust bits to water is a very painstakingly long process by oxygen deprived bacteria and does not release enough ferrous iron to make a difference on the plant.

For anyone curious, I have learned this material from Dr. Nate Storey from Bright Agrotech and the research done by Dr. Ratkocy in the UVI aquaponic project.


If wanting to use a FeDTPA or FeDDHA product, then, for further instructions, I would read the article and watch the videos by Dr. Nate Storey, which is derived using Dr. Ratkocy's research.

For a simpler and more expensive approach, then you can use Seachem's Flourish Iron product, which a 5 gallon jug can be bought on Amazon. With this product, you would only use 8.5 ounces per 50 gallons of water. So, once a year and depending on iron test kit readings, for a 2,000 gallon pond, you would dose the pond with 2.6 gallons (or half of the jug).

For a foliar spray, this can be tricky since the plant must be thoroughly sprayed quite well and not be sprayed with too much due to risk of burning the plant, which is why it should be done in early morning or late evening. So, the product mix must be correct according to the plant. If this is your desire, then I would talk specifically to someone who is more familiar with using it. I would have to do much more research into it to give a better answer.


Important Note. If the Iron product does not mention the chelating agent, then the ferrous iron product is most likely using EDTA, which is what you want to stay away from.

If your local hardware store, such as an ACE affiliate, does not have it, then just ask them to order FeDTPA for you, which they most likely can. From a reference on Dr. Storey's article, here is a DTPA chelated iron that can be obtained from Amazon.


Be sure to use an iron test kit, such as this one by SeaChem. You only want the iron to test around 0.10 mg/l to 1.0 mg/l, except try to stay closer to the 0.10 mg/l level to reduce likeliness of an algae bloom.


Hope this helps.

 

[crsublette]

For some Iron EDDHA products, then I came across these references from Dr. Storey's comments on his iron videos.

Miller FerriPlus

Sequestar Iron 6% Chelate

 

[Priscilla]

Charles - THANK YOU!!! I have been trying to work out what is going on with my water hyacinths and you have solved the problem! THANK YOU!!!

So my first batch I actually posted pictures with some sort of string algae on them - I was suspect of the algae, I knew it looked evil . They were in a sad state. I finally gave up and got a second batch. I have this second batch in floating baskets to more or less protect the roots (they aren't that protected, but good enough). I have noticed the leaves are turning a bit yellow and the flowers are really just half hearted.

I will order that product from Amazon.

Thanks for the time you took to give us this much needed information.

 

[crsublette]

Just be mindful of what you buy and be sure you know your water's pH and make sure your water's pH does not change too much through out the day from early morning to into the evening.

If the water's pH is 7.5 or lower, then the DTPA will work for you, such as the Sequestren Iron Chelate 330 Fe, 5 lb bag found on Amazon.

If the water's pH is above or bounces above 7.5, then the DTPA product above will be much less effective.

If the water's pH is above 7.5 and lower than 9.0 (which it should anyways be lower than 9.0), then the two EDDHA products I mentioned in post#7 will work for you. Actually, after a quick call to my greenhouse buddy, he sells the Miller FerriPlus, which I am surprised and glad to see this.

Ferrous Iron with the EDDHA chelating agent is by far the best one to buy due to how it is more forgiving to all pond's pH ranges. So, if possible, try to get this one.

 

[crsublette]

Also, be mindful of your dosage amount.

Dr. Storey's dosage amount is actually applicable for a system with many many plants so his dosage amount is for 2.0 mg/l.

Personally, I would only do a quarter of his dosage recommendation, wait 24 hours, then perform an iron test on the water using a test kit such as the SeaChem one I hyperlinked above.

 

[crsublette]

For a dosage example, lets use the Ferrous Iron with the EDDHA chelating agent called Miller FerriPlus and here is the labeling on it showing it is "6% iron that is purely chelated by FeEDDHA"

I will use this product in this example since apparently it is quite easily accessible at a local greenhouse even for a little small country bum-kin of a city called Amarillo.

So, using Dr. Storey's dosage and then going to quarter it to be used in my pond...

2.0 mg / L = 7.58 mg / gal

Total Iron in Miller FerriPlus = 6%

Divide 7.58 by 0.06 = 126.33 mg / gal

This means it takes 126.33 mg / gal of Miller FerriPlus to obtain 2.0 mg / L. Now, multiply this by your pond's volume.

If your pond is 3,000 gallons, then ... 126.33 mg / gal X 3,000 = 378,990 mg or 378.99 grams

So, 378.99 grams of Miller FerriPlus to dose a 3,000 gallon pond to have 2.0 mg / L of Iron. Now, I want to quarter this so to only give me 0.50 mg / L.

Divide 378.99 by 4 = 94.7475 grams

94.7475 grams (or 3.34 ounces) of Miller FerriPlus needed to dose a 3,000 gallon pond to have 0.50 mg / L of Iron.


So... For a 3,000 gallon pond, then I would only do a dosage of 3.34 ounces of Miller FerriPlus, wait 24 hours or longer if your pond has little circulation, then do an iron test to double check the Iron concentration in the pond.

 

[crsublette]

Now, some folk might already have enough iron in their source water, except this is not common.

 

[Priscilla]

Okay. My pond seems very steady at 7.5 (as far as matching colors go on a chart, not really an exact science).

I'm sad to see the Miller FerrisPlus is not available on Amazon, I will try to order it from the site you attached. I do think that's my problem, a lot of my plants are just blah with yellow leaves, they are not taking off as I expected them to. The roots systems seem fine, just the leaves are yellow.

I will also buy the iron test kit.

I'm assuming adding iron will not affect the fish in anyway.

 

[crsublette]

According to the SeaChem test kit instructions, this test kit gives a fish "health warning" when the iron concentration goes above 0.50 mg / L stating, "iron over 0.5 mg/L may be toxic to some species and should be avoided." This is why I quartered the dosage recommendation by Dr. Storey so to only be a 0.50 mg / L dosage.

However, Dr. Storey runs his own systems at 2.0 mg / L of Iron with Tilapia, that is a fish from the cichlid family, which is much less hardy and more sensitive to water chemistry than goldfish and koi. So, if Tilapia can tolerate it, then I imagine goldfish and koi would do quite fine.

Although, I read a note by Dr. Storey saying that 2.0 mg / L is the maximum limit; otherwise, it would harm your fish's health.

 

[crsublette]

Iron is an important secondary macro-nutrient for plants.

Correction !!

Iron is actually a MICRO nutrient, the most notable one actually, not a macro-nutrient.

So, as a man, I am driven to explain; thus, the prevalence of iron deficiencies is what is responsible for leading me astray.