Drip....drip....drip

[SallyWho]

I'm setting up the 90g replacement tank for my leaky 120, but I'm having trouble with leaks by a couple of fittings. First I tried using q-tips to apply primer and then more pvc cement to the joints. Then I tried silicone. Then I tried another good, thick, globby coat of silicone. But there's still a slow drip. Do you think it'll seal itself with salt in a few days' time? I really need to get my fish out of their small holding tanks. Thanks!

ETA: the drips are along the return line, so they're kind of under pressure. That would affect the salty residue's ability to plug it up, I'm sure. :/

 

[therootcause]

Hello. I'm assuming you are using slip fittings since you mentioned primer and that all of the PVC is either standard or metric.

Are you able to share a photo? You should never need any silicone when assembling PVC. Are you mixing PVC and ABS?

 

[Mr. Mojo Rising]

You are using a q-tip, and not the brush that comes in the cans of primer and cement? Are you using the Oatey brand?

As a non-DIY guy, my best advice is put the primer and cement on heavy, circle it around many times. The pipe will push in almost a half inch, so lather up the entire half inch. Lather it, don't use it sparingly. Then twist the pipe around when you insert it.

 

[SallyWho]

Hello. I'm assuming you are using slip fittings since you mentioned primer and that all of the PVC is either standard or metric.

Are you able to share a photo? You should never need any silicone when assembling PVC. Are you mixing PVC and ABS?

Yep, slip fittings. Mixing regular rigid pvc with sch40 flex pvc as needed.

The reason for the random extra coupling up there is because the flex pvc was just the tiniest bit too short and I didn't have anything longer. Snipping it and sticking a coupling in there gave me the little bit of extra length I needed to reach the 90s that I have for an over-the-back return.

 

[SallyWho]

You are using a q-tip, and not the brush that comes in the cans of primer and cement? Are you using the Oatey brand?

As a non-DIY guy, my best advice is put the primer and cement on heavy, circle it around many times. The pipe will push in almost a half inch, so lather up the entire half inch. Lather it, don't use it sparingly. Then twist the pipe around when you insert it.

My first go round was exactly as you recommend. I used the included brushes, and held the pieces together for a full 60 seconds. The q-tips were for the second try, when I needed to get in the crevices of the joints without risking dripping any primer or glue into the sump.

 

[therootcause]

Is it leaking at the slip coupling or the 90's? Regardless, cut it out and start over. $30 to run to Lowe's and ditch the flexible PVC and buy a new Union.

 

[SallyWho]

It's leaking at the 90 and at the slip coupling. It's maddening because it used this same flex pvc with my old tank and had zero problems. I used it here because there's a slight angle between the line exiting the sump and the 90 at the terminal end. Rigid pipe would have some trouble with that.

 

[SallyWho]

It's leaking at the 90 and the coupling. It's maddening because I used this same flex pvc for my other thank with zero problems. There's a bit of an angle/bend between where the line exits the sump and the 90 at the terminal end- rigid pvc would struggle with that.