Aquaponic Gardening

A Community and Forum For Aquaponic Gardeners

Hi all! I'm a noob to the community, so please accept my apologies if this has already been covered elsewhere. Does anyone have experience with liquid sealers like drylok and bluemax? The system I'm building will use galvanized steel stock tanks (got a deal on them), and I don't want to leave the zinc coating exposed in my tanks. Any one who has used these or a similar product, PLEASE chime in. Or paste a link to the existing thread.

Views: 1963

Reply to This

Replies to This Discussion

I have never used the products you are inquiring about but I have an alternative. I have successfully used paraffin wax to seal my concrete tanks from leaching. It comes in large blocks and easily melts for paint on applications. I apply a coat then melt with a heat gun to insure no holes then add a second coat. It would be best to rough up the surface prior to application.

That seems like a brilliantly cheap alternative, but I fear that Sacramento's summer temperatures would creep too close to the wax's melting point for my comfort. Especially if there is any direct sunlight on the steel tank. Nonetheless, an excellent suggestion that I will file for a later application.

Unless the sun will heat your water to the point the fish and plants will cook it probably won't be an issue. Paraffin's melting point is well over 100 degrees.The sides of the tank are cooled by the water inside. Painting the outside white will help reflect light/heat.

Paraffin might work for tanks that are always full of water but if doing flood and drain grow beds as well, something else might be better.  The Paraffin is definitely a good alternative for the concrete tanks/beds but melting the wax in is labor intensive.  I'm not sure how well ti would work on the metal, probably worth some testing if materials are on hand for some small scale trials.

You might look into having coatings professionally sprayed into the tanks if there are a lot of them of different sizes.  Or there are probably some pool paints and epoxies that are potable water grade that would work.  Or they do make tank liners that would be replaceable and good for any tanks that are less than perfect since the coatings won't seal holes very well.

Good luck in your research, sorry I don't have any personal experience with and of the mentioned products but you certainly do need to coat or line galvanized tanks before use with aquaponics.

I'm not so much worried about the heat building up in the tank, just loss of adhesion right on the surface of the metal when it gets hot (110+ deg F air temps are not unheard of).
 
Chris Smith said:

Unless the sun will heat your water to the point the fish and plants will cook it probably won't be an issue. Paraffin's melting point is well over 100 degrees.The sides of the tank are cooled by the water inside. Painting the outside white will help reflect light/heat.

 

I'm

No holes in my tanks, brand new farm supply rejects (dents which were no match for a bodyman's hammer and dolly). I think your potable water epoxy idea might be what I end up doing. A hardened epoxy "shouldn't" leech any solvents or chemicals into the water after its full cure time, whereas a non hardened coating will continue to evaporate solvents for months. Plus, with proper surface prep, the epoxy will only increase the lifespan of the tanks. Thanks Lynx
 
TCLynx said:

Paraffin might work for tanks that are always full of water but if doing flood and drain grow beds as well, something else might be better.  The Paraffin is definitely a good alternative for the concrete tanks/beds but melting the wax in is labor intensive.  I'm not sure how well ti would work on the metal, probably worth some testing if materials are on hand for some small scale trials.

You might look into having coatings professionally sprayed into the tanks if there are a lot of them of different sizes.  Or there are probably some pool paints and epoxies that are potable water grade that would work.  Or they do make tank liners that would be replaceable and good for any tanks that are less than perfect since the coatings won't seal holes very well.

Good luck in your research, sorry I don't have any personal experience with and of the mentioned products but you certainly do need to coat or line galvanized tanks before use with aquaponics.

 Wax may not be the best choice for metal but I bet it would work great. As far as the labor it is MUCH easier than fiberglass. I simply melt it on an old pot using a an old hotplate that I got from a yard sale for $5.  I paint it on at my leisure using a large paint brush. I can keep to liquid for as long as I want. I can let it cool and use it again whenever I want. Melting it into the siding is very easy too. I use a propane weed burner that makes a large job go very quick. A heat gun works well too.

TC may be right for coating a metal tank but as she suggested it is worth am experiment.

I just used the paraffin to coat a cement BSF bin. Not sure if the Soldier flies have a ph preference, but didn't want to clean it out and coat it later. Seemed to coat it well, thanks for the tip Chris.

Hey Fishy, I understand Joel Malcolm in Australia used galvanized tanks when he started.  Might check to see what he coated them with.  He runs the website/forum backyardaquaponics.com.

The galvanised tanks used here in Australia are manufactured from zincalum metal which is lined with a "plastic" coating.... a food grade polymer film...

 

They're refered to as "aquaplated"... here's a link to the manufacturer and product... http://www.bluescopesteel.com.au/files/dmfile/AquaplateSampleWarran...

 

Precoated tanks would've been REALLY nice, and I'm not sure anyone in the US is making these. I'm working with what I have, which is your standard, galvanized steel, livestock water trough.

I left the tanks in direct sunlight for about 20 minutes today and they were nearly to hot to pick up. My concern with the wax is that the area of the tank above water level will get hot enough to melt the layer in direct contact with the steel, and slip off into the tank. Perhaps I burned my butt too many times as a kid on the old steel playground equipment, and I'm just paranoid.

I don't really have a budget which allows me to experiment, so my hope was to find a solution which would work without question.

Fishy, a lot of aquaponicists here in Australia have used "SikaTite-BE" , a water based bitumen emulsion "modified with acrylic latex polymers"....to seal old galvanised or concrete tanks...

It is non-toxic, non-leaching, and approved for use in potable water situatuions... and proven to be fish safe...

http://www.sika.com.au/cmc/Datasheets/tds/SikaTiteBE_tds.pdf

 

There must be similar "bitumen" paints available over in the US.... don't know how they might relate costwise compared to EPDM liner.. but might be worth checking out...

Reply to Discussion

RSS

© 2020   Created by Sylvia Bernstein.   Powered by

Badges  |  Report an Issue  |  Terms of Service