Algae clogging skimmer net

[UK Sub]

Help!
I've had my 28x20ft pond for about 10 years now, it has 2 water falls fed from stock tanks, filtration is from a Aqua Ultima II 20000 gal Cyclonic Bead Filter. Water is clear but has some green furry bits on the rocks, some string algae in the water falls. The problem I have is I'm getting my skimmer nets clogged, I have to clean them out about every 3 days now. I'm dosing the pond with Algae Off every week right now. This problem seems to have got much worse in the last year or so, before then I'd go perhaps 3 weeks without any clogging in the nets.
I have not been feeding the fish as temp has been below 55 since the fall.
Stocking numbers are 5, 18" Koi, 5, 18 to 24" Channel catfish and about 50 goldfish, no plants
Water test levels
Nitrate = 0
Nitrite = 0
Ammonia = 0
PH = 8.2
KH = 125
Can any of you more experienced knowledgeable pond types help me, is this a common problem, and how do I get it resolved?
Any advice/ideas would be gratefully received.
TIA
Jon T

 

[BKHpondcritters]

This time of year it's not uncommon to have a bloom of string algae. As a cool water grower, it tends to get going before the bulk of (more desirable) perennial plants/annual floaters get going. The telling statement you've made is this: "no plants" I will beg to differ..... You DO have pond plants - you have algae. How deep is your pond & what is the total water volume? You've got a decent fish load, and they are all producing waste. Plants are what "eat" that waste. Without some other form of plant life, I'm afraid you're going to have to put up with some algae.

 

[Mmathis]

Ditto what @BKHpondcritters said!

 

[UK Sub]

This time of year it's not uncommon to have a bloom of string algae. As a cool water grower, it tends to get going before the bulk of (more desirable) perennial plants/annual floaters get going. The telling statement you've made is this: "no plants" I will beg to differ..... You DO have pond plants - you have algae. How deep is your pond & what is the total water volume? You've got a decent fish load, and they are all producing waste. Plants are what "eat" that waste. Without some other form of plant life, I'm afraid you're going to have to put up with some algae.

Hi, Thanks for your reply's
The volume is roughly 9000 gals, when I said, no plants, I lied a bit, I have the 2 300 gal stock tanks feeding the waterfalls, I have plants in them, but not the main pond. Water Iris, hyacinth...
Would adding plants to the main pond resolve my issue?

 

[BKHpondcritters]

More plants are (almost) never a bad idea, but again, this time of year when things aren't really growing fully yet it's pretty common to have some string algae. I'm not sure what 'Algae Off' is, but if it's an algaecide you might want to rethink using that. If it kills off some of the algae, the dead algae simply adds additional nutrients to the water, which in turn feeds more........ yup, algae!