Aquatic plants brown edges and dying. Tried and tested many things already.

[Aleks]

Hi all,

I am completely puzzled. For over ten years, every year, come July, I've had a gazillion plants, selling them and giving them away. This year, they are brown and miserly, and I don't know why. Here is what I know.

* Water tests perfectly. No nitrate/nitrite, maybe that's the problem?
* Fish are happy. Plenty of koi, goldfish, and turtles for the pond size.
* Added fertilizer with iron, which seemed the obvious problem, which if anything is making things worse and definitely does not help.
* The reeds in the filter are growing. Are they taking away the nutrients? I've never had this many reeds. If that's the issue, I'll ditch them tomorrow. In the bug that has iris and reeds, the iris are not doing so great either this year. The other tub with pond lilies and hiacynth is doing fine.
* Water hiacynth in filter are doing better than in pond, which does point at nutrient issue.
* Both hiacynth and potted iris are doing poorly. Iris didn't even flower! Usually, by now, its huge, even with what the fish are nibbling off. In fact, I usually don't feed much this time of year because there are so many plants to eat.
* Plants in nearby tubs are doing fine.
* Plenty of oxygen in water. I oxygenize and I tested.
* I treat water when topping off pond.
* I feed the animals every day, just pellet food plus veggies once or twice a week.
* I clean the filter whenever it slows down, like I've always done. Backwashing the filter semi-regularly, and take it apart once a year, like I've always done.

What's different from last year? and previous years?
* Reeds in filter are bigger. Wasn't a problem last year or the year before.
* I am doing partial water changes more often, because that became a problem last year for the fish when it was hot.
* Added oxygenation, because that became a problem with the fish last year. Probably too much compost at the bottom.
* Got rid of water lettuce, because it was a pain, didn't have that first few years, then got some in trade, then got rid of it again.
* Cool spring, but that would just cause slower growth...

It's probably not a simple thing, but I am looking for ideas on what else to try.

Any ideas on what to try? What am I missing?

Thanks, Aleks

 

[Mmathis]

Hello and welcome!

Can you give us some information about your pond and set-up....you’ve told us a lot about your plants, but......

1. How big is the pond— gallons, dimensions?
2. What filtration do you have?
3. Where do you live?
4. How many and what size fish do you have?

 

[Aleks]

1. How big is the pond— gallons, dimensions?

About 1700 gallons, 3 feet deep.

1. What filtration do you have?

Biological. Large.

1. Where do you live?

California. Silicone Valley.

1. How many and what size fish do you have?

4 Large Koi. A bunch of goldfish, some very large and old, some smaller. Many mosquito fish. 6 Turtles.

 

[Lisak1]

Welcome @Aleks !

Thanks for the detailed information - very helpful to solving this mystery.

The additional aeration can be eliminated - that wouldn't slow plant growth.

The reeds in the filter MIGHT be an issue - how big are we talking?

Water changes - probably not, as many ponders do regular water changes and don't notice any negative effect on plants.

It could just be a weird weather year - lots of gardeners have noticed slower growth, lack of blooms, etc. Cool spring, too much rain, slow start to warmer weather... who knows. Where are you located?

Can you post a few pictures?

 

[MitchM]

You said you backwash your filter, but you only list a biological filter. How do you backwash a biological filter?
Are the dying plants sitting in 10 years of detritus buildup? What plants?
What are the numerical test results?
A more complete description of the pond setup would help.

 

[addy1]

Welcome to our group!

Where are you located?

Said California, silicone valley.

My pond plants, yard plants have all been off this year.

 

[sissy]

reason I put a pump in the bottom of my filters .I turn water on for my hose and then plug the pump in and then put spray nozzle on a hard spray towards the bottom of the filter .I collect the water for my garden .I also turn the pump off that goes to the filter.Ben doing it this way since 2007

 

[Lisak1]

Welcome to our group!

Said California, silicone valley.

My pond plants, yard plants have all been off this year.

Oops! I missed that!

 

[Mmathis]

Is your biological filter a bog or a Skippy-type?

 

[Panzer13]

I wonder if you just don't have enough nutrients to go around to all the plants. The reeds in the filter may be taking the lions share and not leaving enough for the rest of the plants.

 

[sissy]

yep my plants in the filter can use up most of the stuff to feed the plants in the pond .In spring I put plants in a stock tank with miracle grow and if I see them suffering I will take them out and throw them in it for a couple of days

 

[Aleks]

Pictures:
https://photos.app.goo.gl/oLasfN4HCqtFRysa7

Pond is about 1700 gallons, has been running for 12+ years.
4 large koi, a bunch of large, old goldfish, 4 red-eared slider turtles, and lots of mosquito fish
This time of year, water is murky with floating algae

The purpose of the floating "islands" is to provide some shade, protect some of the plants from being eaten, and provide additional spawning area for goldfish.

The filter is a large box with filter mat material and an external pump. Custom designed to go with the pond.
Plants in filter do better than plants in pond. Plants in tub separate from pond do fine. Plants in other tub, that also has reeds, don't do as well..red herring?

I backwash by reversing flow and dumping outflow into my yard for irrigation. Once a year or two I actually take the thing a apart and rinse the muck off the filter material. Don't like do do this necessary chore, because lots of critters live in filter, including dragondfly larvae.

pH - normal (varies by time of day, of course)
No nitrate / nitrite
No phosphates
No chlorine
Oxygen levels are good
No Ammonia
Alkalinity fine
Water on the hard side
No hydrogen sulfide

 

[Aleks]

I added fertilizer to the floating "islands" directly, with iron, and it doesn't seem to make a difference.

 

[Lisak1]

They are definitely struggling. I am curious why your water is so full of algae with all those plants. Something isn't adding up. If you have that much excess nutrients in the water that algae can take over, why are the plants not happy? They do look to be needing iron, but nitrogen would also green them up. You said you tested zero for nitrates/nitrates - again, curious with all that algae. Phosphates can also cause green water... what's the pond bottom look like? Any build up of muck or debris? You said "too much compost" - do you mean just plain old muck? Does your pond always turn green at this time of year?

And the plants don't just look yellow, they look burned - has it been super hot? Or did the fertilizer maybe cause the burning?

I wonder if your bio-load has just exceeded the ability of your filtration to handle the pond - four turtles plus four koi and a plethora of goldfish just might be too much for your size pond and filter. I don't know much about turtles except I have heard they are big waste producers.

Sorry for so many questions - this one is a puzzle!

 

[Brian B]

Hey all,

I am a novice at this for sure but....

How hot has it been there? I am in the Sacramento area, and it has been upper 90s to well over 100 degrees here for the last couple of weeks. I moved one of my patio umbrellas over to partially cover my pond to prevent anything from being scorched (and to prevent green water algae bloom).

Any chance it has been hotter than normal there too? I know the Bay Area is generally cooler, but in that area, a heat wave tends to have more effect than it does here.