Trying to kill algae and pump jammed

[texmaster]

Hi folks,

My Koi pond is 12x10x3.5 deep. I've had a major string algae problem since it started to warm up. Its so bad I can't even get it off with a power washer from the sides or the rocks. I had some algae-off a friend gave me and added it to the water. The next day the waterfall connecting to my main filter system was trickling at best. It connects through a 4 inch bottom with bubbler drain up to a Aqua Ultima II Filer, through a Evolution 55 Watt UV clarifier and back to the waterfall. Total distance about 25 feet round trip. The pump has been undersized since I installed it only putting out about 1/3 of the water the skimmer pump is producing. The skimmer pump is a rock star. Its a SKP5000. The main filter pump is a 4200SEQ12 Sequence 750 Series External. I've actually purchased another more powerful 5800 and it should be here this week. I bought it before this problem arose. I'm just glad I have a 2 pump system or I'd be in real trouble or at least my fish would be. I've left it off but every 12 hours I gave it a shot and now nothing comes out but the pump is running so I turn it off fast. Even when I tried to clean the Aqua filter I could only get a trickle from the exhaust when trying to clean with the pump on and the water was pretty clear. I have a strainer connected to the pump but it had next to nothing in it. A minor bit of algae. I'm stumped. If anyone has any ideas I'm listening.

Here are some pics if they help but they aren't recent just for perspective.

The pump thats clogged is the right waterfall.

 

[DrCase]

You need to figure out we're the water is stopping, most likely it's at the bottom drain. If you can take the leaf basket out and put a water hose into the inlet and blow the water back to the drain, hold a rag around the hose to build up pressure

 

[texmaster]

You need to figure out we're the water is stopping, most likely it's at the bottom drain. If you can take the leaf basket out and put a water hose into the inlet and blow the water back to the drain, hold a rag around the hose to build up pressure

I'll give that a shot thank you!

 

[texmaster]

You need to figure out we're the water is stopping, most likely it's at the bottom drain. If you can take the leaf basket out and put a water hose into the inlet and blow the water back to the drain, hold a rag around the hose to build up pressure

I forgot I've got a check valve installed so I can't go through the pump side. I'd have to do it from the bottom drain

Wouldn't the cleaning of the aqua filter be strong however if it was just a clog in the line from the pond and since the pump is hooked directly to the filter system but it still produces almost no water when I turned it to rinse mode

 

[DrCase]

Some takes it just takes a little push backward to open a drain
Or water line to let the crud flow through

 

[texmaster]

Some takes it just takes a little push backward to open a drain
Or water line to let the crud flow through

But how can I push it through from the top when I have a check valve installed at the bottom of the pond on its way to the top?

 

[DrCase]

That is a problem. You might have to go for a dive with the pump running and go through the bottom drain

 

[texmaster]

That is a problem. You might have to go for a dive with the pump running and go through the bottom drain

After getting a quote for 600 dollars just to clean the pond I agree. I'm going to do a complete drain and scrub it right. Once its clean I'll tackle the clog from the drain.

 

[DrCase]

That would work
Suck the drain clog out with a wet vac