Fine Dirt in Pool

[EHam]

I have what seems like dirt or sand at the bottom of pool. I thought it was pollen, but I think it may be dead algae. It is a tan/gray color. I’m going to shock the pool for a few days and backwash

 

[mburn16]

The locals around here aren't such a fan of the word "shock". But if the algae is already dead (and I agree with that assessment), "shocking" is redundant. The purpose of shocking is to kill what is living, not get rid of what is already dead.

Vacuum and backwash.

 

[triptyx]

The locals around here aren't such a fan of the word "shock". But if the algae is already dead (and I agree with that assessment), "shocking" is redundant. The purpose of shocking is to kill what is living, not get rid of what is already dead.

Vacuum and backwash.

Without test numbers, we don't know if there is still any live algae. Giving someone this kind of advice without having test numbers is a poor idea.

EHam - first of all, welcome! Your first step will be to get us a full set of test numbers from an approved test kit - a TF-100 (most reagents for the money) or a Taylor K-2006C (make sure it's a C so you have enough reagents).

You can get the TF-100 here: TFTestkits.net
The 2006C can be obtained through Amazon or a favorite supplier.

The reason we want numbers is that we don't know what's going on with your pool. The reason we want you to test and not some random high schooler at the local store is that the stores often get it wrong (and they have no incentive to get it right).

Once we have a full set of test results, we'll be able to get your problem all taken care of (and keep it that way). While you're waiting on a kit, we need the following:

1. Please update your signature in the forums with your pool info - you can use my signature or another poster's.
2. Once we have a pool size, I can suggest a certain amount of liquid chlorine or plain, unscented bleach (not "fabric guard" or cloromax, and not splashless or EZ-Pour please) you can add each day until your test kit arrives.
3. Time to start reading:

Pool School - ABCs of Pool Water Chemistry
Pool School - How to Chlorinate Your Pool
Pool School - Defeating Algae

 

[EHam]

I will update my info and order a test kit. Right now my info from the pool store is:
ph:7.7
TA: 100
FC: 7.7
TC: 7.7
CYA: 62

- - - Updated - - -

 

[AimeeH]

HI and welcome to TFP

That really looks like algae to me. As triptyx pointed you to good links for reading, I'd start there. We generally don't trust pool store tests and advocate you get a good accurate test kit and take over your pool from the pool store. Pool School - Test Kits Compared

 

[EHam]

The picture makes it look darker than it is. It is tan in color and disappears when I brush it...can’t even pick it up! I thought it may be mustard algae from what I read online, but the guy at the pool store said it looked like dead algae.

 

[AimeeH]

Well......with a good test kit to accurately test your chlorine to within .5 ppm of chlorine, you could conduct an overnight free chlorine loss test (OCLT) to confirm. Your chlorine is consumed by two things in the pool--sunlight and organics. You can test your FC after sundown but before sunrise and if your FC loss is 1or less then you know it is not organics--ie. Algae.

I suspect algae. But a good test kit would help you rule that out.

 

[EHam]

Mustard algae?

 

[AimeeH]

Mustard algae?

I would doubt mustard algae as that is more rare than people think. The solution is the same though. Getting a good test kit and following the SLAM process.

 

[triptyx]

Mustard usually "sticks" to the walls - it's not something that loosely pools on the bottom like that.

So with a 9000 gallon pool, let's start by adding about 1/3rd of a jug of liquid chlorine or plain, unscented bleach (not splashless, EZPour, Cloromax, or fabric guard) a day to the pool. This should keep everything in check until the test kit arrives. Once the kit arrives, run the tests and we'll get you on the way to a sparkly pool.

 

[Husky25]

As you describe it and from the pics, it looks like regular, run of the mill, dead algae to me.

Do what triptyx suggests while waiting for your kit.

In the meantime, you could also give the pool a good brushing, particularly the walls. Then try vacuuming slowly to waste, once everything settles on the bottom again.