Sand Filter ineffective and somewhat noisy

[Johnbednarski]

Hi everyone, my issue is that my pool remains cloudy following around a month past season opening. The chemistry is balanced. I have not seen incremental improvement of the cloudiness in comparison to prior years. I’ve begun to suspect that my sand filter is not removing debris from the water, or if it is, it is performing at a poor level.

I’ve noticed that my Hayward filter and top-mounted spider valve has a rather noisy rattling sound near the top of the filter, where the spider valve is mounted in my setup. I wonder if it’s sand futzing around the top of the filter, making the noise. I’ve wondered if there‘s an issue between the internal connection between the spider valve and the waterflow distribution piping that sits beneath the valve, internal to the filter.

I‘m thinking about removing the spider valve and do a sandflush with garden hose, the sort of sand cleaning that’s described elsewhere on the forum. By removing the spider valve, I could do an inspection of the piping to see if there’s a problem.

Does this plan sound like a proper next step? Would you recommend I proactively buy a replacement piping setup - assuming something like that is sold independently of an entirely new sand filter - before I begin the sand flush process?

 

[PoolGate]

Your filter has very little to do with water clarity. Can you post a full set of water tests?

 

[Texas Splash]

I would be concerned about two issues:
1 - Water chemistry. You don't appear to have the PoolMath APP, so as PoolGate noted, we should see a full set of water test results.
2 - As for the noise at the MPV, it's possible there is some play in the stem due to a, old spring or some other issue. Opening it to inspect is fine to check.

The cloudiness can very likely be a chemistry issue. Test results would be our first place to start since it's generally the easiest and very common. If we rule out chemistry, then perhaps your MPV is loose inside and not closing the ports properly thereby allowing water to flow improperly.

 

[Texas Splash]

If we rule out water chemistry, then when you go to inspect the MPV you might as well do the deep clean as well.

Deep Cleaning a Sand Filter

This post will walk you through the anatomy of a sand filter, and then provide a video at the end for how to deep clean your sand filter. The filter used in the photos and videos is a Hayward S180T top mount sand filter. The images are of a similar filter. Obviously not all filters are...

www.troublefreepool.com

 

[Johnbednarski]

Your filter has very little to do with water clarity. Can you post a full set of water tests?

Sure. FC 4.0, pH 7.0, TA 50, CYA 40. I’ve since added a box of Borax. These values are about 4 days old. I add 0.5 gallons of liquid chlorine 10% every other day.

I should clarify that, as is usual when I open, there was clearly an algae load, despite having winterized the water prior to closing. this is not uncommon. The greeen color abated the day I opened, following a high dose of chlorine. I vacuumed the pool to waste and have performed the usual filtering ever since.

Once killed, now-dead microoriganisms continue to float in the water, creating cloudiness, yes? In years past, the once-opened pool water clears over maybe a week of filtering. that has not been the case this year, hence my puzzlement about why.

 

[Texas Splash]

Once killed, now-dead microoriganisms continue to float in the water, creating cloudiness, yes?

Dead algae will certainly remain in the pool until filtered out. It may look white or light gray in appearance. But more importantly, did you pass the Overnight Chlorine Loss Test? That is one of the SLAM passing criteria to ensure all live algae has been eliminated. If you skipped the Overnight Chlorine Loss Test, I would encourage you to do that before you start tearing apart the filter and MPV. Doesn't cost you anything other than a little time. Excessive organics are often transparent and not clearly visible to us like green algae, but an OCLT can help ID it.

 

[Johnbednarski]

Thanks everyone.

1). I’ll plan to do an OCLT. I don’t live at the property where the pool is located, so this is a bit of a challenge to get done immediately.

2). One of my gate valve isn’t sealing off properly. I’ve ordered one and expect it to arrive this week. As I have to disrupt the plumbing anyway, I’ll probably go ahead with cleaning the sand filter at the same time.

I’ve used TFP’s iOS Pool Math for 3-4 seasons now. I track two pools. Nice app.

Appreciate the insights -

John