- May 13, 2020
- 56
- Pool Size
- 5300
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Intex Krystal Clear
Hello All, 
I have a 14'x36" Intex above-ground pool with a sand filter. It has the salt system generator installed and working also. I Recently replaced the sand media with new sand from pool supply store. The old sand was in good condition.
The pool has an aftermarket skimmer installed AND I left one of the original intake ports to make sure the pump has sufficient inflow.
I test my water once every few days lately, trying to find the issue using the Taylor test kit and my levels are posted below:
Water Temp Avg 80 degrees
FC 3
Combined Chlorine 0
pH 7.8
Alkalinity 120
Hardness 100
CYA 40
Chlorine generator runs 6 hours per day, filter runs 8 hours per day.
Pool in direct sun most of the day.
Treated with an Algaecide for precaution.
The problem I am having is I can vacuum the pool , shock it and within a few days there is a greenish/brown dust on the bottom of the pool. It stirs up easily and makes the water cloudy. It seems that the sand filter does not trap it but when I backwash it there is green coming out of it for about 10 seconds or so daily. I'm stuck in a vicious cycle of 2 days of clear water then the rest of the time with crappy water and it's been this way since I installed the pool 3 years ago.
Is this dead algae? Dormant algae? It takes about two days for it to settle to the bottom so I can vacuum it.
Pollen is low here at the moment.
I am aware that I have to discharge to WASTE when vacuuming.
I appreciate any insight someone can offer as I am at a loss as to what can be done differently. Am I having micro-blooms then shock is making it fall out? HELP!
I have a 14'x36" Intex above-ground pool with a sand filter. It has the salt system generator installed and working also. I Recently replaced the sand media with new sand from pool supply store. The old sand was in good condition.
The pool has an aftermarket skimmer installed AND I left one of the original intake ports to make sure the pump has sufficient inflow.
I test my water once every few days lately, trying to find the issue using the Taylor test kit and my levels are posted below:
Water Temp Avg 80 degrees
FC 3
Combined Chlorine 0
pH 7.8
Alkalinity 120
Hardness 100
CYA 40
Chlorine generator runs 6 hours per day, filter runs 8 hours per day.
Pool in direct sun most of the day.
Treated with an Algaecide for precaution.
The problem I am having is I can vacuum the pool , shock it and within a few days there is a greenish/brown dust on the bottom of the pool. It stirs up easily and makes the water cloudy. It seems that the sand filter does not trap it but when I backwash it there is green coming out of it for about 10 seconds or so daily. I'm stuck in a vicious cycle of 2 days of clear water then the rest of the time with crappy water and it's been this way since I installed the pool 3 years ago.
Is this dead algae? Dormant algae? It takes about two days for it to settle to the bottom so I can vacuum it.
Pollen is low here at the moment.
I am aware that I have to discharge to WASTE when vacuuming.
I appreciate any insight someone can offer as I am at a loss as to what can be done differently. Am I having micro-blooms then shock is making it fall out? HELP!
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