How do I replace water in an in-ground hottub

[ingroundspa]

Hi there!

We have an in-ground hot tub whose water turned green. Unfortunately, I ended up adding a bunch of dichlor shock to increase the FC level. Now, my CYA level is out of the charts (according to the FAS-DPD test). Approx 200ppm is my estimate based on retesting with diluted with tap water. PoolMath says I need to replace 80% of my water.

Question is how do I exactly go about replacing water? Here is what I am thinking. Does that sound reasonable? Am I missing any important steps?

1) Turn off power to filter/heater (unplug power cord)
2) Plug skimmer port with a rag
3) Siphon off water from spa
4) Add new water
5) Power on filter/heater

The system consists of:
- In ground spa (Tahoe Fiberglass Inground Spa Pool - 450 Gallons)
- Filter system (Pentair Clean & Clear)
- Pump (Not sure of model)
- Gas heater (Raypak 105B Cast Iron)

 

[mknauss]

Welcome to the forum!

So this is a standalone spa? If so, why plug the skimmer? You can siphon it if you have an elevation drop near the spa.

It appears you test with a TF100 or K2006? That is great.

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Take care.

 

[ingroundspa]

Thanks. It is K2006.

This is a standalone spa. I thought plugging the skimmer might be a good precaution to avoid an air lock. Is that not necessary?

 

[mknauss]

Cannot see how you could get an air lock. When you refill it will fill everything up. Once the pump is running crack open your air bleed on your filter until water comes out of it and things should be back to normal.

You will want to add stabilizer and then SLAM the water once refilled. The algae you had is in the filter, pipes, etc. Should go quickly.

 

[Akathisia]

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