Backyard Aquaponics
A place to discuss aquaponics

Perhaps this needs to get stickied into useful info or something as I'm sure lots of new people have questions about the many ways to deal with plumbing.

Here are a couple things I have done or used.

I have not been able to find "top hat gromits" but I have found uniseals which can be gotten here
http://www.aquaticeco.com/subcategories/829/Uniseals/uniseals/0

They are inexpensive rubbery gromit like things that can work through a tank wall as thick as 1/2 and inch. I have even used them in my pond liner/plywood grow beds and so far no leak problems. It can be difficult to push the pipe through the uniseal if you don't have a good angle and leverage to do it but they do work.

I have also used normal inexpensive bulkhead fittings and they are easier to deal with since they are specifically made for the purpose but then you need fittings to attach pipe to the bulkhead and it all costs more.

When dealing with things like barrels or tanks that you can drill a hole in, I have drilled a hole just barley big enough to thread the appropriate size pvc fitting thought and in many cases, if there is no real water pressure, that is all I did. Having a conduit nut on the inside and some aquarium silicone will make it more secure and take care of leaking in most situations. One trick is to make the hole slightly small and warm up the plastic with a blow dryer or heat gun a little before threading the fitting into the hole. When it cools, it is a tight fit and now has threads molded into it.

My aim is often to use the least number of fittings to do the job well and keep it simple. The uniseals are good for this as the uniseal is pretty inexpensive and you need no other fitting to connect to the tank, just the appropriate size pvc. Quite handy for overflow pipes as you can just slide the pipe through to the correct height. Rubbing alcohol can be used to help get the pipe to slip through the fitting without worry of soap residue from the windex they recommend hurting your fish.

it looks like there are plenty of methods that work. i'm leaning toward the straight threads using a gasket and silicone to help seal. the only drawback i see here is being able to find a gasket the right size, but it shouldn't be a problem. thanks for all the tips.

Dont worry about the gasket just plenty of silicone [never had a leak in 2 years

i wanted to try to see if i can get away with just the gasket. the only argument i have for this is the flexibility of replacing the fittings in the future. why? i have no clue, haha, just trying to think ahead. silicone seems to be more of permanent solution and may make it harder to remove the fittings in case i wanted to...

Wots a straight thread? Wot is another type

the silicone is pretty temporary if you decide to remove the fitting, it will still come out fine. Only real drawback I see with silicone, is the fact that you need to let it cure for a fairly long time before adding water or connecting up to a system with fish in it and there is the problem with the standard lack of patients.

As for gasket material, often times you can look in the plumbing section of the hardware store and find a package of assorted gasket sizes. As to if any will be right for your situation is another story. I have gotten a flat sheet of gasket material and cut my own before.

Another thing I have done is use thread seal paste in connections I didn't want to glue and that seems to have worked where there isn't pressure involved and doesn't seem to have hurt the fish.

I will just reiterate...

PVC Male Threaded Coupler
PVC Female Threaded Coupler
White Plumbers Tape
Rubber 'O' Ring

Will never leak... Used this method in Sumps, aquariums, overflow boxes, AP system MK 1,2,3,4 and my current system. No problems!

AHH all threads go roundin circles,,,but whta's being talked about here is, tapered thread....
some threads remain the same diameter throughout their length, others star ta little smaller and end up a little bigger , clear as mud??? Exagerated ,, think cone/funnel.

My saying is do you best and silicon the rest.

hi guys, can someone please confirm for me? are the smaller pipes in the pics below (care of F&F thanks, hope I haven't breached any copyrights laws ) are 20mm and the larger one 100mm? I plan to use these in my GB's in the same manner as F&F has done.

cheers Taz

You got it

cheers mate!