Brown gunk on the bottom of pool

[rox29160]

I have an above ground pool with a saltwater chlorine generator. The ph and chlorine levels have always been really easy to maintain with this system. I think I still may have some type of algae though. It is this brown "stuff" on the bottom. After you vacuum it up, it takes about 3-4 days before it starts reappearing. I have even "hyper" chlorinated a few times just to see if that would make a difference. It has not done anything, other than give me a bright yellow solution with my test kit for a few days, lol. Any ideas on what it could be or how to get rid of it? Oh yeah, if you leave it in there for more than a day or two, it gets harder to remove. It almost acts like it stains the liner.

[Watermom]

Hi and welcome! Can you tell us what kind of pool you have, what kind of filter you have and size of pump. Also, we need a current set of test results taken with a drops-based kit. We will also need to know exactly what all you have put in your pool meaning ingredients, not just product names or "shock."

Sounds like you are using an OTO kit. You really need a better kit. The one we recommend is the Taylor K-2006 or 2006C (same kit, larger bottle of some reagents). If you buy it through the Amazon link in my signature, the Pool Forum makes a little money on the sale which helps us keep this form online. Only buy if the seller is Amato Industries, however. Some other sellers are substituting the K-2005 which you do NOT want. If Amato isn't listed, wait a day or two and try again. They seem to restock pretty quickly when they sell out.

Repost with requested info and somebody here will try and help you.

[PoolDoc]

Hi Rox;

I just move your thread where you can post -- sorry, but I upgraded your user status, without moving the post.

Regarding the brown stuff, it could be algae, or it could be iron from your fill water. Do this:

#1 - Tell us what your chlorine levels are -- day to day -- using your OTO / phenol red test kit.
#2 - Test your stabilizer level, or get it tested and tell us what it is.
#3 - Assuming that your pool was filled with the same water that goes into the toilet, check the inside of your toilet tank. If it's dark brown, you have iron. If it's not, I need to know if you have a water softener on your water line.

[rox29160]

Thanks for responding Watermom and PoolDoc! Sorry it took me so long to reply back. I couldn't find my original post when searching for it.

Watermom: I have a Intex Ultra 16' x 48" above ground, (5,061 gallons). It has the round accordian paper type "A" filter. I don't know what these are called. The pump is 1,500 gph (per Target's website), also by Intex. The SWCG is Intex Krystal Clear. All I have added to the pool is about 125 lbs of salt and 1/2 lb of cyuranic acid. I did add a gallon of bleach to it while I was filling it up to keep it from getting nasty before the water got up to the inlet of the pump. Since then I have not added anything. You are correct, I have only been using a OTO kit. I have been debating on whether to buy one of the Taylor kits. I am wondering if something other than my chlorine level may be the culprit. Amato is evidently out of the K-2006 kits today, I will check back the end of the week.

PoolDoc: I filled the water from a well so iron could be a possibility. I will test the water tonight and re-post. I do know that the inside of the tank is brown. It is not as bad as some other toilets as I have seen, but it is brown. I started having toilet trouble while I was filling up the pool so I remember very well what it looks like. I don't have a water softener installed. Is there somthing that can be added to the pool water to remove or treat it for the iron?

Thanks again for your help.

[rox29160]

I tested my pool water with the OTO kit I have when I got home from work. The chlorine level is somewhere in the 1.0-1.5 ppm range, which is where it usually is unless it has recently rained. The ph is a little lower than my kit says is ideal, but only by a little. I would say it is around 7.5. The kit says ideal is 7.6. It is hard for me to match up the colors exactly which is why I was already contemplating buying one of the Taylor kits before Watermom suggested it to me in the previous post. The chlorine and ph levels are pretty consistent. It doesn't matter if I test in the morning or in the evening like I did tonight. I don't seem to be losing much chlorine. I only run my SWCG for 2 hours per day. Any more than that and my chlorine readings get up around 5 ppm.

I double checked the tank on my toilet. The "brown" I referred to earlier is a brown ring around the top, at the normal water level, not the entire inside of the tank (if this makes a difference).

I also got in the pool tonight and investigated the brown "gunk" a little. The walls of the pool are NOT slimy at all. I have read that this is an indicator of algae in other threads. The brown stuff looks kind of like dirt, but when you try to pick it up with your fingers, it disintegrates. It is slimy almost like the slimy mud in the bottom of a river. I don't have a lot of it. It is just in small isolated spots on the bottom of the pool about the size of quarters. I tried vacuuming it up, but I have the cheap vacuum that came with the pool. (the kind that connects to the garden hose and then catches debris in a little net) After tonight, I am sure that once the "gunk" is disturbed, it just washes right through the holes in the net.

Any help is appreciated. Thanks in advance.

[PoolDoc]

Could be dead algae -- have you had algae?