Plant issues: hyacinths doing poor; small green flakes

[jimfr]

Two issues which began 3 years ago after we drained and resurfaced our 35 year old pond in(San Diego, California :
1) Hyacinths don't do well, even in summer when average air temp high is low 80s. We bring them into pond in great condition, and over a few months the leaves start to brown, bulbs start to die, and they don't seem to multiply much. Some occasionally flower.

2) Have tons of loose dark green flakes, each flake a few millimeters wide covering entire bottom. When scoop out in a fish net, the flakes have the consistency of watery oatmeal. Until about 6 months ago, the flakes would float to surface during the day and sink to the bottom at night... no longer does that... flakes now all stay at bottom.

Hoping someone can advise me on this.

Other info: 350 gallon block wall pond with no pumps or filters. Water depth about 13 inches. Water is very clear, no algae, fish (we only have mosquito fish) are fine, other plants (mostly lilies and some tall long shoot plants) are fine, water test strips show everything in the "good" range.

 

[j.w]

and welcome @jimfr
I don't have Hyacinth but the flakes could be excess build up of nutrients that are rotting that have settled. Not sure tho, just a guess.You have no filter and no circulation so it all just rots.

 

[Mmathis]

Hello and welcome!

I’m not sure exactly what it is you are asking. Your pond is 350 gallons and you resurfaced it 3 years ago. Some plants are doing well, but you can’t grow water hyacinth? Assume you mean water hyacinth and not the bulbs you plant in the ground……. And now you have green flakes that accumulate on the bottom?

What did you “resurface” the pond with (and why)? If you don’t have fish, then there might not be enough nutrients in the water to adequately feed the hyacinth. Water hyacinth is a pretty straightforward plant, but it can be picky at times. I have no clue about the green flakes, sorry.

Please post some pictures of your pond that we can use as a reference.

 

[jimfr]

Yes, wondering why water hyacinth don't do well (see pics). See picture #1 of green flakes on pond bottom. The odd thing is why do these two issues only exist after the drain and resurface 3 years ago, yet was fine for the previous 32 years before that.

The drain and resurface was done to repair a minor leak. Old inside coating was stripped and new Pond Shield epoxy coating applied by a local pond company.

There are probably 20 to 30 mosquito fish in the pond.

 

[j.w]

Yes, wondering why water hyacinth don't do well (see pics). See picture #1 of green flakes on pond bottom. The odd thing is why do these two issues only exist after the drain and resurface 3 years ago, yet was fine for the previous 32 years before that.

The drain and resurface was done to repair a minor leak. Old inside coating was stripped and new Pond Shield epoxy coating applied by a local pond company.

There are probably 20 to 30 mosquito fish in the pond.

Hard to tell from the photo but it kinda looks like those green flakes are some kind of living plant life. Pick some of it out and get a real close up photo of it if you can. Does it squish into goo if you smoosh it?

 

[jimfr]

Here's a photo after I scooped a few tablespoons off bottom and dumped it. The finger photo is after squishing some together my fingers.

Also, I tried pond algaecide last year many times (at that time I had some algae issues), they barely have any effect on the green flakes.

 

[Lisak1]

Your plants need fertilizer. If you don’t have fish in the pond you can pull them out and put them in a bucket with some water soluble fertilizer. Let them soak for 24 hours, RUNSE THOROUGHLY and return to the pond.

The green stuff is just algae. One of a billion kinds. Green stuff in a pond is to be expected and actually necessary.

 

[j.w]

It looks like dying or dead algae (maybe why it is now only on the bottom). Maybe why nothing will kill it as it is dead already and you need to vacuum it out?
I did find this online:

Algae and other submerged aquatic plants float in water during day and sink at night. This is because, during day time, algae and other submerged aquatic plants undergo photosynthesis which releases the O2 as one of the end product which makes them float during day time. During night time, these organisms consume O2 which is released during day time and sink at night.​

 

[jimfr]

Your plants need fertilizer. If you don’t have fish in the pond you can pull them out and put them in a bucket with some water soluble fertilizer.

My pond does have fish