Backyard Aquaponics
A place to discuss aquaponics

Have been looking for a suitable sump to incorporate into the AP system and the home hydro...

Came across a 650L (approx) Cement Pit on eBay - 900mm high 1200mm long 600mm wide .... which will fit just perfectly under the two hydro trays....

Question.... I've read of various ways to treat "new" cement tanks to combat the lime leaching and pH drag....

Everything from soaking pineapple skins in them for several days... to acid washing with hydrolchloric acid, which I have....

Should I go down this road.... or just coat the whole thing with sikaflex, or whatever it's called?

Coating might be the easy and quick method. Kinda like the idea of using it as is. Maybe see what the effects are and if they can be handled. If it was something that was only a problem for a short period of time. Would filling it and letting it sit for a while with something to get it to age faster be an option.

Plus 1 for sikaflex

Probably not an option Duff... from what I've heard cement tanks can drag pH to around 9.0.... as this will become the reservoir for the hydro trays.... I'd prefer to have the pH between 6.5 and 7.5 at worst...

sikatite is the stuff you're talking about - black goop

That's the one... thanks Jaymie....

C1... do I need to soak/cure the tank (to seal it) for a while before using it.... or just whack it on???

That one looks like it is fibre reinforced Rupe, any idea how old it is?

Got no idea Sleepe, description said "used"... will contact the seller tomorrow... was browsing and it only had 3 mins to go.... picked it up for $10.... and I'm going to be driving past the location on Thursday anyway...

asbestos reinforced sump tank - nice .

I suggest cutting it in half with a circular saw

That what you reckon it is VB... asbestos....

Just joking Rupe - but some of the old cement pipes and shit do have asbestos in them (like the fibro sheeting). Can't tell from the picture though.

Even though it said "used" ... doesn't look that old... wouldn't have even thought about the possibility of "asbestos"... although I did initially think it was fibreglass from the picture... listed as a "cement pit"...

Yeh - doesn't look old at all. Looks like the modern day ones they use to me - kinda thin. I'd coat it as stated though.

Am unsure when they stopped asbestos reinforcing, but it was a fair while ago. Only reason I asked was because of its thinness which requires fibre reinforcing and usually more cement in the mix. As it is older and if it has been used for water it is likely it has become stable. Will wait to see what C1 says re coating.

Cement tank should be a good structure if you put a liner in it.