Sand filter question

[HardTrance9]

Hi guys!

Hopefully I can get a little help with this:

There is one pool that has:

Pump
----

STA-Rite
JWPA5FL-A
1.5 HP

Filter
------
Interwater
Model 190TS




The filter however is too small and needs to be replaced as it 's causing the pool no to be cleaned properly and black algae started appearing since the original cartridge filter was exchanged for this smaller sand filter.

The pool capacity is 11,000 gallons and it is a SWG.

Now a bigger sand filter wants to be installed instead but I am not sure which capacity could be the correct one. There is a measurement of GPM's and we found some selling a filter in good conditions, used, but maybe is too big??

http://www.hayward-pool.com/prd/In-Grou ... 5516_I.htm

http://www.hayward-pool.com/pdf/literat ... L05-06.pdf


Any idea on what oversized filter capacity should do the work for this 11,000 gal. pool?

The current filter does does 40 GPM

The filter in the lings does 90 to 130 GPM

Any suggestions?

Thanks !! :?:

 

[JasonLion]

Having a filter that is too small is not going to cause black algae, or any other kind of algae. You get algae when the FC levels are too low, either from adding too little chlorine or from bad circulation causing locally low FC levels. Black algae in particular can only get going when you have dramatically too low FC levels over a fairly long period of time.

I recommend a filter with about 300 lbs of sand (about 150 kg), or larger. However, the Interwater Model 190TS should work, though require more frequent backwashing, as long as it isn't broken.

 

[257WbyMag]

Relocated to Equipment forum as topic is equipment related.