Auto topup

[Biggyg]

has anybody made this them selfs ?
If so how did you do it and cheapest way to do it .

I cant imagine it being that difficult

 

[Mical]

Many people make them with a small pump and a timer. It gets a little tricky getting the times correct because evaporation rates vary with temperature and depending on tank size it could have adverse effects on salinity. Others use a small pump and a float valve/switch - again it can be tricky & risky. Now a days there's some pretty reasonable priced ones that work without alot of hassle - IE: https://www.bulkreefsupply.com/duetto-dual-sensor-complete-aquarium-ato-system-xp-aqua.html

I'm sure in the UK you have some options...

 

[mikereefing]

There's a low tech water bottle auto top off that I got off Amazon a while ago. It works well and it was only like 13 dollars for the adapter. All you need is a water bottle with longer threads on top. I use it for my nano frag tank

 

[R.Weller]

We use gravity & a gate valve. It creates a constant drip. Very cheap & never fails.