On 07/06/2021 21:59, Fredxx wrote:
On 07/06/2021 08:46, Tim Lamb wrote:
In message , Fredxx
writes
On 06/06/2021 21:52, Tim Lamb wrote:
Snippage.
https://www.plasticdrainage.co.uk/ac...nd-downpipe-bl

ack.html

The access plate would make a handy template for making the holes.
Â*Hmm.. That might do!
Â*The tank is an ancient rectangular 4' x 3'6 x 3'6 riveted
galvanised steel construction I have been using as a secure chemical
store after fitting a hinged lid. The exterior is sound but the
inside had some rusting hence the glass fibre.
Â*The fill pipe could be a sliding fit in the lid and your *hatch
plate*Â* outlet extended and insect proofed above planned water level.
Â*So far, I have not found a bulkhead or tank connector adaptable to
68mmÂ* although I take the point that the plastic can be stretched
with theÂ* application of heat.

IBCs (Intermediate Bulk Container Tank) are cheap and don't rust,
plus if translucent you can see the water level. Just a thought.

Indeed. 1000L and there are numerous adapters available for piping the
threaded outlet.
However, I already have an almost suitable, larger tank:-) Left over
glass fibre kit and the potential satisfaction of re-purposing a large
lump of otherwise scrap steel.
Currently the collected rainwater goes to a soakaway.

Can you insect-proof the top of the drain pipe?

I have lots of fine mesh plastic netting bought to protect garden
produce for tank vents. Gutter and down pipe not practical but I
assume insects lay their eggs in standing water.

A film of oil tends to stop that! It does mean the overflow must dip
below the surface and have a anti-syphon feature

Paraffin is more usual than lubricating oil. Diesel would do equally
well. Not so much that it prevents egg laying, it stops mosquito larvae
from breathing through their snorkels when they hatch.