A lot of useful information posted from you guys, thanks very much.
The system was running continuous for 3 days and is now on two 4 hour cycles morning and afternoon and hopefully that will be reduced to 3 hours in a week or so. Initially the water was very green but its virtually clear now but I will add just a bit of chlorine to help get the level about right and then keep an eye on it every few weeks. Re adding the acid - is it sulphuric, hydrochloric, either, or something else?
The person who mentioned putting two copper spikes in the ground brought me two earlier today, so we have sunk those in the ground and run a copper cable to the two rail fixings, so I will see what if any impact it has.
Dannie Boy wrote:A lot of useful information posted from you guys, thanks very much.
The system was running continuous for 3 days and is now on two 4 hour cycles morning and afternoon and hopefully that will be reduced to 3 hours in a week or so. Initially the water was very green but its virtually clear now but I will add just a bit of chlorine to help get the level about right and then keep an eye on it every few weeks. Re adding the acid - is it sulphuric, hydrochloric, either, or something else?
The person who mentioned putting two copper spikes in the ground brought me two earlier today, so we have sunk those in the ground and run a copper cable to the two rail fixings, so I will see what if any impact it has.
Hydrochloric, Dannie. Don't know the % of concentration but it's very strong and great caution needed when pouring not to have drops splash up onto you or onto any metal or wood. It's OK on stone and plastic. Fumes can get you as well. If it's a very humid day and you unscrew the top, get ready for a small vapour cloud. Pete
Governments are instituted among Men, deriving their just powers from the consent of the governed. Source
Dannie Boy wrote:A lot of useful information posted from you guys, thanks very much.
The system was running continuous for 3 days and is now on two 4 hour cycles morning and afternoon and hopefully that will be reduced to 3 hours in a week or so. Initially the water was very green but its virtually clear now but I will add just a bit of chlorine to help get the level about right and then keep an eye on it every few weeks. Re adding the acid - is it sulphuric, hydrochloric, either, or something else?
The person who mentioned putting two copper spikes in the ground brought me two earlier today, so we have sunk those in the ground and run a copper cable to the two rail fixings, so I will see what if any impact it has.
Hydrochloric, Dannie. Don't know the % of concentration but it's very strong and great caution needed when pouring not to have drops splash up onto you or onto any metal or wood. It's OK on stone and plastic. Fumes can get you as well. If it's a very humid day and you unscrew the top, get ready for a small vapour cloud. Pete
I already have some Pete, but typically Thai, there is no label on it but it is exactly what you say, heavy fumes and "gas" flowing from the container when you take the lid off. They have used this to clean off the sand wash and even diluted, it still bubbles as soon as its in contact with the sand wash, so I will treat it with respect. In between my post and your reply I did a google search and discovered it was hydrochloric acid, but grateful for your confirmation.
Take a look at the below thread Dannie at your leisure. I wish you years of carefree enjoyment with your pool, but if in a few years down the road your sand wash that is submerged or constantly in contact with water starts to fail, please let us know. SJ has had no problems but I'm still not convinced that my problem wasn't caused by the salt, or maybe a combination of salt and a not so good sand wash mix during construction. Pete
prcscct wrote:Take a look at the below thread Dannie at your leisure. I wish you years of carefree enjoyment with your pool, but if in a few years down the road your sand wash that is submerged or constantly in contact with water starts to fail, please let us know. SJ has had no problems but I'm still not convinced that my problem wasn't caused by the salt, or maybe a combination of salt and a not so good sand wash mix during construction. Pete
Thanks Pete, I remember reading that thread - oh the joys of having a swimming pool!! Like you and many others, we do have sand wash on the tops of the steps, but no other sand wash in direct contact with the water so will have to monitor how it lasts.
In the pool this morning with daughter and realized that I have some stainless in there as well. The overflow trench empties into an underground tank prior to the filter via 2 x 4" vertical pvc pipes. I've capped both pipes to avoid debris from going into the tank with those stainless 4.5" diameter screen mesh strainers that they sell to cover your kitchen sink drain. They've been in there a year and have water flowing through them 8-9 hours a day, and they're as shiny as the day bought. I don't think they are high grade stainless, the cost is 100 something Baht each. Don't know what conclusion to draw from this related to your corroding ladder. Pete
Governments are instituted among Men, deriving their just powers from the consent of the governed. Source
prcscct wrote:In the pool this morning with daughter and realized that I have some stainless in there as well. The overflow trench empties into an underground tank prior to the filter via 2 x 4" vertical pvc pipes. I've capped both pipes to avoid debris from going into the tank with those stainless 4.5" diameter screen mesh strainers that they sell to cover your kitchen sink drain. They've been in there a year and have water flowing through them 8-9 hours a day, and they're as shiny as the day bought. I don't think they are high grade stainless, the cost is 100 something Baht each. Don't know what conclusion to draw from this related to your corroding ladder. Pete
This is the ladder after one week, and even though the rust is not very clear in the photo, it doesnt look as though it will last long at this rate, in fact i am thinking of taking it out already.
I think that you will find that the steps are aluminium, not stainless steel. They are acting as a sacrificial anode. I have not seen s/s with that pattern on it, but it is very common in aluminium.
May you be in heaven half an hour before the devil know`s you`re dead!
Nereus wrote:I think that you will find that the steps are aluminium, not stainless steel. They are acting as a sacrificial anode. I have not seen s/s with that pattern on it, but it is very common in aluminium.
I think you're right Nerus, I can't get a magnet to attach to the steps, but somebody who looked at the steps correctly pointed out that the rust is almost exclusively where the welding was done - not sure if you can weld with SS rods?
I've also seen SS with strong plastic steps. If Nereus is right and the steps are aluminum, I don't imagine any problem with SS rails and plastic steps. However, I guess good to see what the step fasteners are made of. I imagine this type more readily available here than polymer. Pete
Governments are instituted among Men, deriving their just powers from the consent of the governed. Source
Nereus wrote:I think that you will find that the steps are aluminium, not stainless steel. They are acting as a sacrificial anode. I have not seen s/s with that pattern on it, but it is very common in aluminium.
I think you're right Nerus, I can't get a magnet to attach to the steps, but somebody who looked at the steps correctly pointed out that the rust is almost exclusively where the welding was done - not sure if you can weld with SS rods?
Both stainless (most) and aluminium are non-magnetic, so a magnet will not be attracted to either of them.
And yes, stainless can be welded, either with a stick type rod, or better, with some form of gas inner shield such as TIG or MIG.
From your photo the rails appear to be stainless steel.
May you be in heaven half an hour before the devil know`s you`re dead!
Nereus wrote:I think that you will find that the steps are aluminium, not stainless steel. They are acting as a sacrificial anode. I have not seen s/s with that pattern on it, but it is very common in aluminium.
I think you're right Nerus, I can't get a magnet to attach to the steps, but somebody who looked at the steps correctly pointed out that the rust is almost exclusively where the welding was done - not sure if you can weld with SS rods?
Both stainless (most) and aluminium are non-magnetic, so a magnet will not be attracted to either of them.
And yes, stainless can be welded, either with a stick type rod, or better, with some form of gas inner shield such as TIG or MIG.
From your photo the rails appear to be stainless steel.
The rails are definitely stainless but the treads could well be aluminium. Not sure what if anything he can do, but will ask the guy who made them whether he can suggest a solution. They were actually "free" in as much as we ordered a gate for the drive and after we agreed the price, I managed to twist his rm into supplying the steps FOC - but I guess you get what you pay for!!
but it is exactly what you say, heavy fumes and "gas" flowing from the container when you take the lid off. They have used this to clean off the sand wash and even diluted, it still bubbles as soon as its in contact with the sand wash, so I will treat it with respect. In between my post and your reply I did a google search and discovered it was hydrochloric acid, but grateful for your confirmation. 
Pete 
