# Other Aquarium Forums > Equipment and Accessories > DIY Projects >  DIY Auto Water Top-up

## wfc31

My <S$50 DIY water level top-up.
Bought the floats at SimLim Tower at S$20 each, 12VDC relay.
Re-use of old un-use internal filter mini-pump.
Plastic L-bracket
Screw & nut, some screw spacers.

Two floats connected at series with same level, it is for safety purpose, in case one float fail to cut-off the relay when water level high, the second float still will able to cut-off. IF both floats fail, then gonna flood already lo, but i think will not so bad luck la.

Pls refer to the pictures attached, any question are welcome.

----------


## tawauboy

tested your rig already?
will the water surface movement (due to fans) cause the pump to cut in and out frequently?

looks like you are well versed in diy...

----------


## neon

Hi,

where did u buy the 12 vdc and how much does it cost ?

thx !

Cheers

----------


## tawauboy

> Hi,
> 
> where did u buy the 12 vdc and how much does it cost ?
> 
> thx !
> 
> Cheers


12 vdc relay or float or ???

----------


## ranmasatome

Wow!! this looks nice!! :Smile:  :Smile:

----------


## solonavi

Nice effort. Probably you wan to place the two float switch further apart to cater for uneven water level.

Cheers
JC

----------


## neon

> 12 vdc relay or float or ???



Sorry , I meant both the float as well as the relay .

Thanks !

Cheers

----------


## tawauboy

> Sorry , I meant both the float as well as the relay .
> 
> Thanks !
> 
> Cheers


guess you didn't read the 1st post.
you can get these devices from sim lim tower.

----------


## eric_kclee

> My <S$50 DIY water level top-up.



Hallo, Have you consider the float mechanism in our toilet reservoir before? it is much more simpler and need no electricity. This mechanism is so proven that many ponds and fountain out there is currently using this mechanism. If you worry about faulty valve, you can build a double protection or tripple protection one.

Ya, be carefull with your mechanism, cuting in and out at the brim of contact, this may cause arcing (contact bounce/ sparking) and overheat and cause little fire. Switching on/off and A/C is more complicated, need to design circuitory to prevent arcing.

----------


## coolbucks

Hi All bros,

I have also tried to diy an top up water sys but it don't work....Have an 10A 250VAC/280VDC OLGEN by (2N DC 12
v) relay with base switches and float switch but it don't work... can someone assist me ....

I have connected the relay in this way by the shop owner advice. point 3 n 4 connected to 'live' and 'netural' , point 5 n 6 connected to an pump and point 7 n 8 connected to float switch... Tested 'live' current is there but no current in point 5 n 6 ....

----------


## tawauboy

> Hi All bros,
> 
> I have also tried to diy an top up water sys but it don't work....Have an 10A 250VAC/280VDC OLGEN by (2N DC 12
> v) relay with base switches and float switch but it don't work... can someone assist me ....
> 
> I have connected the relay in this way by the shop owner advice. point 3 n 4 connected to 'live' and 'netural' , point 5 n 6 connected to an pump and point 7 n 8 connected to float switch... Tested 'live' current is there but no current in point 5 n 6 ....


based on your description, you are lucky that you did not blow up something.
do you have a schematic of your diy? do you have a 12v supply for energizing the relay coil?
i am not able to tell you the exact connections as i do not know the relay connections. the normal connections would be similar to what is posted in post 1 above.

----------


## solonavi

Hi Guys, I'll not advise those not trained (professionally) to try DIY an electrical equipment especially voltage convertor is involved. For those looking for a top up equipment, spend slightly more than $100 can solve ur problems and u can have a peace of mind.

Check out the Tubby by Coral Labs, a sponsor in SRC (marine forum).
http://www.sgreefclub.com/forum/inde...showtopic=6143

What does the TUBBY do?

The TUBBY is a automatic fresh water top up device which will replace any lost water due to evaporation in your marine tank. It is maintenance free and relies on 2 float switches to detect your water level in the tank. Once the level drops, it will activate a attached powerhead (not included) in a freshwater container. The powerhead then pumps freshwater back to the main tank to replace the evaporated water. Hence maintaining salinity. (salt does not evaporate)

Some TUBBY users also use the TUBBY to help in their monthly water changes. The possibilites are up to your own imagination.

Who needs a TUBBY?

1) Those going for holidays
2) Those going for BMT or reservist
3) Those who are frequently not at home to do water top ups
4) Those who want to maintain salinity and prevent swings when pouring freshwater all at once
5) Those who want to treat the freshwater with Anti Chlorine first.
6) Those who want a easier maintenance free tank.
7) Those who cool their tank using fans hence high evaporation rate
 :Cool:  Those with small tanks where water level changes (salinity) are stressful to corals and fish.

Why this Product is better than the competition if any? :

1) Float switches run entirely on 12v DC and on very low current.
2) There is a fuse to prevent any short circuits of your connected powerhead
3) Output supply to powerhead is totally isolated until BOTH float switches activate. (Both neutral and live are isolated)
4) 2 Float switches which turn on the pump only when BOTH are activated as added safety. (Prevents false activation by snails, floating algae etc)
5) Runs on a regulated voltage transformer able to take 110-240Vac and can operate 24hrs continuously. No risk of overheating or fluctuating voltages etc. Typical AC-DC transformers are not designed to run continuously for 24hrs a day.
6) Branded relay used in military and commercial applications with very high mean time before failures. (high MTBF)
7) 30 days manufacturing defect warranty.


What you will need to start:

1. TUBBY unit.
2. Fresh Water container (preferably of 20 liter volume at least).
3. A powerhead pump (rated at least 600L/hr to 1200L/hreg SICCE NOVA).
4. Hoses to connect the pump to your tank/sump.
5. A fish tank (of course).

----------


## solonavi

Another alternative is the "DE Auto Top Up".
http://www.delightings.com/index.cfm?GPID=14

Automate your aquarium water top off with DE Water Level Controller. By using stainless steel probe, you will achieve precision control and you will not have to worry unlike using float switch, which can be sensitive to water movement or get choked. This unit also comes with an option to manually over ride the top up if required and you can also off the unit when not in use.

Best part of all, this unit comes complete with everything you need.

1) Fully Automatic Water Level Controller Unit
2) Stainless Steel probe for Sump Tank
3) Stainless Steel probe for Water Reservoir (Optional)
4) Rio90 Feeding pump (1.5watt, 323l/h)
5) Small diameter Feeding Hose (2meters)
6) 6 Suckers (For probe)
7) 3 spare fuse & 2 screws for mounting

----------


## coolbucks

my attachment for the diagram for the connection layout...did not connect any 12v adaptor...

----------


## wfc31

tawauboy,
water surface movement does not causing the system to cut-in and cut-off frequently because the water movement is so gentle and not like the wave maker in the marine tank.
yup, i think before to make a float guard to reduce the water movement, but at last i give up as the initial set-up already in best operation. 

neon,
the 12vdc relay can get it at Sim Lim Tower at different price, depend on the manufacturer, model and which shop u go, it may from price of $4 to $12, i got mine at $8.

eric_kclee,
the toilet use float mechanism is seem to be big for my tank. And it needs of water supply pipe line, very inconvenience.
u mean the cut-in and cut-off mechanism in the relay contact will cause arcing? Maybe i need to refer to my Electrical Engineer regarding this problem, he may give me an idea. But, my factory's electrical panel (i work as a technician in Facilities Dept) got lot of this type of relay, which cuting in/out with 230v also, seem to be no problem there. 
Anyway, thanks to ur advice.

----------


## eagleray

For those who has basic soldering skills ... you can consider getting the following circuit 

http://www.futurekit.com/detail.php?id=88
FK425: WATER PUMP LEVEL CONTROL
Got it from space electronics in sim lim towers (cannot remember how much, probably in the SGD$5-7 range)

This allows you to set a high/low water level mark. It will keep refilling till the high level mark and will not start re-filling until the water level falls below the low water level mark 
The kit does not come with float switches, so you still need to purchase the pair of float switches seperately


2. For EXTRA protection, you can get one of those standard electronic timer for 3 pin plugs ... and set it to turn on the circuit & pump for 2-3 mins max a day, depending on your refill amt/timing.
I got the digital type as the analog type has a minimum 15 mins setting.
(I use it more to save electricity ... no need for the circuit to be on the entire day as we only need to fill water once a day)

As Solonavi has advised, for those who do not understand basic electronics, please buy commercial products .... 240V13A not something to play with, esp near water :>

----------

