New Acrylic aquarium - I'm back after 30 y.

[Hong Kong]

 

[Hong Kong]

Before was going slowly but much more double than now see photo...
Here in Serbia very difficult to find flow restrictor will try remove all cartrdiges placed all new no issue 10 micron is 2 euro carbon is 8 euro and IOn one i purchased in Netherland shop 36 euro...
Membrane old one i can use again no issue lets see whats clodgged by carbon...that i didnt flushed need separate box before placing in RO.

 

[Hong Kong]

And dirty water is very fast and strong pressure...

 

[Hong Kong]

I read manual to clean flushing valve 400 with vinegar acid...but i didnt produce many liters in this time 1-2 years...as soon want filling first test water 200 liters in tank...

Will anyway drop this water and use for flushing 40 kg of Bali sand.See bellow photo.

What you suggesting to do?
And whats happened what carbon dirt clodgged?

 

[griss]

I would say there’s likely a clog somewhere but finding it may require to investigation. My first guess would be somewhere in the membrane housing so, that’s where I’d start.