Non Toxic Water Sealer For Cement Tanks

[jaideeguy]

I have a koi pond that is leaking and I have to re-seal the whole inside. In the past, I have used an additive to cement and painted a thick coat on and had to neutralize the alkaline leaching for a few days with vinegar until it became neutral.

I really don't have the time to wait, because my koi are in a small holding tank and crowded conditions and I am thinking of using an acrylic paint to seal the tank. Local hardware store carries an acrylic roof and tennis court paint and am wondering if that would be safe for my fish?? I've used it for painting cement floors in the past and it is a tough, long lasting paint.

I don't want to use an oil base paint because of the smell and long drying time.

[Maizefarmer]

Aaaahh .......... good man - me too, also have Koi carp. How deep is your pond - as a Koi keeper you'll understand that question.

Any hardware store - ask them what they have for sealing leaks on concreate domestic water storage tanks. My experiance is that if its good enough for domestic water storage tanks, it'll be good enough for Koi tank.

Another option is to seal up with silicon, allow the skin to form, and then apply some wide gaffer tape (any similar type plastic or adhesive backed woven cloth tape). Over lap it a few times - so that the tape spreads out a good few inches each side of the seal - and that should it just fine. In a weeks time come back and strip off the gaffer tape.

[Somtham]

I have a koi pond that is leaking and I have to re-seal the whole inside. In the past, I have used an additive to cement and painted a thick coat on and had to neutralize the alkaline leaching for a few days with vinegar until it became neutral.

I really don't have the time to wait, because my koi are in a small holding tank and crowded conditions and I am thinking of using an acrylic paint to seal the tank. Local hardware store carries an acrylic roof and tennis court paint and am wondering if that would be safe for my fish?? I've used it for painting cement floors in the past and it is a tough, long lasting paint.

I don't want to use an oil base paint because of the smell and long drying time.

One of our neighors is a fish breeder and has about 60 concrete tanks. He paints all of them with a blue epoxy based paint after the concrete cures. Check out your local hardware/paint store.

rgds

[jaideeguy]

Since my OP, i found a shell product with a familiar name 'flintkote' #3 that my local hardware shop has. it's a bitumous product with microfibers that is applied by brush and goes on thick and the shell website says that it is non toxic and safe for water tanks. only drawback is that it is black in color and I wanted a lighter color.

anyone use this product??

Edited August 7, 2008 by jaideeguy

[Tywais]

Since my OP, i found a shell product with a familiar name 'flintkote' #3 that my local hardware shop has.

I have a similar problem and looked up the above product. Would also like to see feedback regarding it and if lighter colors are available.

http://www.flintkote.co.nz/watertank_treatment.html

[Maizefarmer]

Since my OP, i found a shell product with a familiar name 'flintkote' #3 that my local hardware shop has. it's a bitumous product with microfibers that is applied by brush and goes on thick and the shell website says that it is non toxic and safe for water tanks. only drawback is that it is black in color and I wanted a lighter color.

anyone use this product??

Yes - Its excllent stuff for dealing with concreate water tanks that have any degree of pourisity, and it lasts forever ...... actualy its not black - believe it or not once applied it forms a skin that goes brown!!

I did think of it, but it has one problem - the skin remains sticky/tacky for a few weeks and can stick to the fish if they rub themselves against it. Other than for that there's not much around that will beat it.

[jaideeguy]

Just painted my koi tank with the flintkote #3 after patching obvious cracks with epoxy. the paint went on smooth and dries really fast, but I'll wait 24 hrs to cure altho the shell website says 10-12 hrs....just to be sure and then test it with a few guppies before i return my koi to the newly painted tank.

The wife saw the can and said 'yea, that's what Thais use to paint the insides of their ongs [round cement water tanks], so it sounds like the stuff tu use, altho it's brown in the can, it dries to black and may make the koi stand out more.

One word of caution....use rubber gloves, as I got a little on my fingers and once dried the stuff won't come off with water, soap, vinegar, or even acetone. Now i'm stuck with black finger tips.

cost of 3.5 lt...370THB

will post if the guppies survive in a couple of days

[jaideeguy]

Maisefarmer....we must have posted at the same time. How do i remove this stuff from my fingers...you're right, it is still sticky, altho dry, but nothing will remove it. Am i branded for life???

[jopham]

Hi jaideeguy

you might have to change your signater to nuwdam.

[jaideeguy]

OK, I found the stuff to disolve the flintkote.....baby oil!! In my last post, my fingers were sticking to the keyboard.

maisefarmer, I don't want my beautiful koi to get stuck to the sides and/or get brown spots on thier beautiful red, white and gold colors. any way to speed up curing process?? with no water, it should speed it up..correct?

nuwdam?? black...what?? wife is not here to ask if you insulted me or not.....I'll assume not.

[Tywais]

nuwdam?? black...what?? wife is not here to ask if you insulted me or not.....I'll assume not.

Black fingers (though not complete in this form, could mean toes too).

Was wondering how much area you had to do and how many liters required to do it?

[jaideeguy]

'Was wondering how much area you had to do and how many liters required to do it? '

Approx 1/2 of the can [3.5lt] covered approx 3 sq mtrs, one coat.

[Tywais]

'Was wondering how much area you had to do and how many liters required to do it? '

Approx 1/2 of the can [3.5lt] covered approx 3 sq mtrs, one coat.

Thanks for that. If you have a chance to take a photo of before water is added and after that would be useful (for me) to see the effect.

[Tywais]

Sorry about being a nuisance, but did you use a standard paint brush to apply it and how would a paint roller work. My area is rather large.

[Maizefarmer]

Maisefarmer....we must have posted at the same time. How do i remove this stuff from my fingers...you're right, it is still sticky, altho dry, but nothing will remove it. Am i branded for life???

Noooooooooo.......... use a paint brush, not a roller - and then throw it away afterwards because its going to be good for nothing else except maybe getting a fire going!

er.............thats just the problem with the stuff I was trying to convey - it's so dam_n sticky, and it's going to stick to your fish as well if they rub themselves against it. Under the skin - which is just that, a skin which stays thin for an awful long time (though once on its on and seals very well), it stays moist and sticky.

The only stuff I know that will clean it off anything it gets onto (including skin) and break down the stickyness is Hammerite brand Paint Thinners.

[Khonwan]

I used Flintkote #3 several times a few years ago on my water tanks and roof. I’m sure I used petrol to get the stuff off my hands – not pleasant (it burns and isn’t particularly healthy!) but effective. Baby oil sounds much more pleasant though.

Rgds

Khonwan

[jaideeguy]

I did use a paint brush and it did clean up as latex paint does with water ....if you do it immediately after. It does skim over fast and in 3 minutes, you will get sticky fingers like I had.

This morning it was still tacky and flexible. i could easily cut into it with my fingernails, if i wanted nuwdams again, but will let it sit a couple of days at least before adding water. I'll try to get some before and after water and fish are in fotos for you tywais.

Wife says vegetable oil also works to clean up after....cheaper than baby oil.

[Maizefarmer]

I did use a paint brush and it did clean up as latex paint does with water ....if you do it immediately after. It does skim over fast and in 3 minutes, you will get sticky fingers like I had.

This morning it was still tacky and flexible. i could easily cut into it with my fingernails, if i wanted nuwdams again, but will let it sit a couple of days at least before adding water. I'll try to get some before and after water and fish are in fotos for you tywais.

Wife says vegetable oil also works to clean up after....cheaper than baby oil.

.....................you can wait a week or longer, if you wish - it will still be tacky and flexible - just like it is today.

[jaideeguy]

If that is the case, then I'll fill it tomorrow and suffer with brown spotted koi. today, after 24 hrs with the fan blowing on it, it is still the same tacky. Will report any dead guppies before I return koi to their newly painted pond..

[Maizefarmer]

I think you'll be fine - I was taking a worst case case scenario because Koi can be real sensitive - if they are rubbing themselves aginst the tank they have parasites irritating them and its time to change water and/or throw some cooper in - in reality chances are youre going to ave no problems and fish and tank are going to be just fine.

[jaideeguy]

Well, the 10 guppies survived the night and today I'll replace the koi. One thing that I would have done differently would be to do 2 coats instead of one, because There is still some slight seepage....just a little and maybe algae will slow it down. At any rate, I can live with it and hopefully the fish can too.

maizefarmer....do you know if the flintkote can be top coated with any other paints....latex would be easiest and I think the most elastic...but I never could find any info regarding toxicity of latex paints except that some paint pigments can be toxic.

Actually the black coat looks good as it adds depth to the pond and I think the koi will be nicely contrasted with black color, but I have a high calcium content in my water and it will eventually get white stains from calcium scale.

[ozzydom]

Well, the 10 guppies survived the night and today I'll replace the koi. One thing that I would have done differently would be to do 2 coats instead of one, because There is still some slight seepage....just a little and maybe algae will slow it down. At any rate, I can live with it and hopefully the fish can too.

maizefarmer....do you know if the flintkote can be top coated with any other paints....latex would be easiest and I think the most elastic...but I never could find any info regarding toxicity of latex paints except that some paint pigments can be toxic.

Actually the black coat looks good as it adds depth to the pond and I think the koi will be nicely contrasted with black color, but I have a high calcium content in my water and it will eventually get white stains from calcium scale.

Be careful if using paints marketed for roofing as some have a fungicide additive to deter algae growth.

[Maizefarmer]

Well, the 10 guppies survived the night and today I'll replace the koi. One thing that I would have done differently would be to do 2 coats instead of one, because There is still some slight seepage....just a little and maybe algae will slow it down. At any rate, I can live with it and hopefully the fish can too.

maizefarmer....do you know if the flintkote can be top coated with any other paints....latex would be easiest and I think the most elastic...but I never could find any info regarding toxicity of latex paints except that some paint pigments can be toxic.

Actually the black coat looks good as it adds depth to the pond and I think the koi will be nicely contrasted with black color, but I have a high calcium content in my water and it will eventually get white stains from calcium scale.

To be honest JaideeGuy I dont know the answer to that. Off the top of my head I would think not - not because of any chemical conflict between them but because the Flintkote is so flexible it will not offer a top coat a stable base to bind to - result: water is eventually going to get between the top coat and the Flintkote.

I can't see much harm in trying though .......................

[Khonwan]

Full spec (2 page pdf) on Flintkote #3: http://www.shell.com/static/bitumen-en/dow...ote3bitemul.pdf

Rgds

Khonwan

[Maizefarmer]

Cheers Khonwan - there it is guys, the full spec: everything you ever wanted to know about the stuff.

[jaideeguy]

The koi are back happy at home!! yesterday, after the guppies survived a couple of days, I tried three smaller koi and they survived overnight and today I added the 20 [or so] remaining Koi and they seem happy with their new enclosure. I do like the black look as it sets off the color of the koi.

If I get any 'floaters', I'll post...but sofa so good!!

I'll try to get a foto and post for tywais...

[Tywais]

The koi are back happy at home!! yesterday, after the guppies survived a couple of days, I tried three smaller koi and they survived overnight and today I added the 20 [or so] remaining Koi and they seem happy with their new enclosure. I do like the black look as it sets off the color of the koi.

If I get any 'floaters', I'll post...but sofa so good!!

I'll try to get a foto and post for tywais...

Thanks for the update.