Available in 13mm, 19mm and 25mm barbed tails as well as extensions and screens to keep media out of the drainage.
These fittings are designed for a flood and drain system. The hole would be ideal at 30-31mm. 32mm is about the maximum.
These fittings are ideal for flood and drain and should always be located above the tank in case of the odd drip while the growing area is full of water. Their low design will allow almost all the water to be removed from the tray. They do not leak in the situation they are designed for which is directly above a reservoir.
A large weight of the water can produce a drip if left for a period of time so flood times of more than 15 minutes should be avoided.
If only used as a drain, e.g. drip fed system drainage, then the chance of a drip is very very small.
These fittings are not pressure rated, and should not be used below the level of water - e.g. connecting two tanks of water together. The types of fittings that are used in this kind of situation have a rubber seal on both sides and can be tightened much tighter than this type of design.
They are very good for trays and containers that will need drainage or flooding over a short term.
Q: why is the Australian symbol no longer on the fitting
A: We have not changed suppliers. They are still quality Australian made fittings. They will not suit submerged applications as that is not what they have been designed to do. They are designed to fit Hydroponic drains and flood and drain trays.