Pool is clear but attached spa is green

[Sal512]

I have a salt pool with DE filter. I run the filter everyday for 7 hours pool is clear, but lots of green algae in the spa. Its been around for 3 weeks now, brushing and running filter pump is not clearing the spa. Some of the algae stuck to the bottom of spa turned black, i suspect it is due to the high texas temp and sunlight. Its not coming off with brushing. I see new green stuff growing spa. Please advise how to fix this?
Can I drain the spa and use this ‘wet and forget’ mold algae remover on the floor of my spa?

Wet & Forget Moss, Mold, Mildew & Algae Stain Remover 0.75-gallon, 2-pack

 

[Spa Owner]

Is the spa being circulated/chlorinated when you run the pool filter? Can it be? Or is the spa seperate?

No I dont think you should drain and apply the wet and forget to the spa. Wait and give a bit more information first.

 

[Sal512]

Yes, the spa is circulated/chlorinated with the pool. The water flows out of the spa and drops into pool

 

[#40Fan]

Test FC in the spa and pool separately and compare.

 

[jblizzle]

Solution for algae is following the SLAM Process process.

What test kit do you use?
Are you keeping the FC at the appropriate level for your CYA, according to the [FC/CYA][/FC/CYA]?

 

[Spa Owner]

I have a salt pool with DE filter. I run the filter everyday for 7 hours pool is clear, but lots of green algae in the spa. Its been around for 3 weeks now, brushing and running filter pump is not clearing the spa. Some of the algae stuck to the bottom of spa turned black, i suspect it is due to the high texas temp and sunlight. Its not coming off with brushing. I see new green stuff growing spa. Please advise how to fix this?
Can I drain the spa and use this ‘wet and forget’ mold algae remover on the floor of my spa?

Wet & Forget Moss, Mold, Mildew & Algae Stain Remover 0.75-gallon, 2-pack

Something isn't adding up...

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Yes, the spa is circulated/chlorinated with the pool. The water flows out of the spa and drops into pool

This is odd. Why would the spa be green and the pool clear? I agree SLAM would be a good start but there may be more here

Is all the water for the pool going through the spa and into the pool, or is only some of the water going to the spa and most going to the pool?

Normally the smaller volume is clearer and the larger volume off colour. Is the pool definitely clear?
Does the spa get a lot of garden run off into it?

 

[ajw22]

What % output is your SWG set to? I think we are going to find low FC for the CYA. [FC/CYA][/FC/CYA]

Pics of your spa and pool may help us understand the environment it is in.

Regardless, if you have algae in your spa then there is algae in your pool. You need to do the SLAM Process process. Step by step. No shortcuts.

First step is you need either the Tf-100 Test Kit or the Taylor K-2006C test kit. Get the trst kit and post your test results and then we can help you begin the SLAM Process process.

Btw, i use Wet and Forget all around the outside of my house. Great stuff. But it will not work on wet surfaces like in a spa. It needs dry surfaces and the sun to change the PH of the surface to kill mold and mildew.

 

[Sal512]

Thanks for the responses. Posting pics so u can get a better idea

 

[Spa Owner]

Is all the water for the pool going through the spa and into the pool, or is only some of the water going to the spa and most going to the pool?

Spa isnt used much is it?​

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[ajw22]

Can you post pics of your pool equipment pad - pump, filter, and valves?

 

[Sal512]

3 Pics

 

[Sal512]

Its not an easy pad to understand from pics....I inherited this from previous owner of home

 

[ajw22]

You have an interesting problem. The valve splitting the water between your pool and spa is after your filter but before your SWG. Your spa is not getting the chlorinated output from your SWG. Your spa is getting lower FC after the sunlight FC loss in your pool and not being boosted by the SWG.

You had a crazy plumber do that piping. It needs to be simplified and fixed to chlorinate your spa.

 

[zea3]

Test a water sample from the spa for FC and then test a sample from the pool. They are probably very different.

 

[jblizzle]

Looks like algae in the pool too.

Yeah, looks like you need to replumbing to get that swg before the pool/ spa 3way valve.

Or add a spa make up valve from the pool side to the spa side so that you are chlorinating the spa when running in spill over but not when using the spa.

 

[ajw22]

Other option is for Sal to turn off the SWG and do the SLAM Process process to clear the algae from pool and spa and then maintain it as a non-SWG pool using liquid chlorine/bleach until he can get the SWG replumbed.

 

[Spa Owner]

That has to be the most embarassing plumbing ever...I apologise on behalf of the entire industry

 

[Spa Owner]

I think after looking at this the best idea would be to:
- Move the gas heater to the other side
- Move pump to opposite side
- Lift pump up to remove air entrapment and make direct connection to pump suction
- Reposition SWG above top of filter as per requirements to enable complete drain down on pump stop

I think the above gross fixes will remove most of the issues I can see, and remove a lot of complications from the plumbing...and reduce the pools energy consumption as well.
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[jblizzle]

Nothing should "drain down" when the pump stops. Only way anything drains is if there is an air leak.

 

[Spa Owner]

This is how it should be plumbed generally. I think there is another pump in there, but cant tell if that is booster to the spa, heat booster to the gas heater or some other device.

I haven't shown all the valves I would fit, but have shown the extra ones I suggest. Realising configurations may be slightly different, but this is a better lay out by miles.