[fly*]

Yeah I just exchanged it got the 15min one now.

[fly*]

Righty's well that idea worked like a bomb. The fans are switching on and off every 15 minutes and its A.) keeping the temp down to a healthy 25.5 and B.) i'm not losing as much water to evaporaation. Before, every morning and afternoon I would be topping up with 1.5L of RO water. This morning the tanks level was still fine

Next thing i'm gonna try is switching the fan to on for 15min, off for 30min, on for 15 etc etc at night. i wanna see if I can still maintain that temp but run the fans less.

The only thing i'm skepitcal of is the transformer handling the constant on off on off but only time will tell.

[mariusmeyer]

You should only be needing to run the fans while the lights are on. After lights out I reckon the fans can stay off. It will only be the surrounding temp that will effect the tank then. If you want to you could say run the fans maybe 15min and off for 1-2hours during the night. And this only for summer months.

[fly*]

Hey mariusmeyer,

Yeah I thought that would be the case as well, only to find the tank sitting at 28 - 29 in the mornings which is why I started running the fans at night as well. Maybe its just where i'm currently staying atm but man that tank cooks. So it definately needs a fan on it at night, maybe not as intense as when the lights are on but it definately needs some cooling. So intermittent should do the trick and save some water and electricity

I'll be moving hopefully at the end of this month and I know that my new place is defs cooler

[franscubitt]

Fly dont give up on your temp controller.
send me the cct and I will check it over for you.
the best way to insulate your temp sensor is to put it in a straw filled with silicone.
it is a good thing if it takes time for the temp to change then you dont get rapid on/off of your fans.
I have tried the heater stat thing but it is useless and my units I made also have too big a range between on/off thats why I asked a friend to programe a pic for me and do it digitally. when he finishes it! I will send u one. I just got to nag him as he has a new girlfriend

[fly*]

Hey franscubitt

I dont have the cct with me now, its at home so i'll scan it probs tomorrow. My big thing tho is costs. If its gonna cost me more than R800 then I may as well just get a chiller. So far that original thermostat idea set me back about R350 (circuit, spare pots, casing, fans and transformers). So....bar me just having fun with solder I need to decide when enough is enough and start spending cash on a auto top up idea

How much is the digital unit ???

[franscubitt]

it will basically be the cost of the IC and a driver, app R35 I guess.
I just got to get him to finish the damm thing.
Auto top up you buy from ACDC a float switch app R90 and if u are using a small pump you just controll it with the switch. Oh and the cost of a small case to fit it in.
I built mine with an electronic driver switching a relay but I recon it was overkill.

[fly*]

Well i'll be interested in the both circuits if you can supply them ??? and i'm at home today so I wont be able to scan that other circuit in

[franscubitt]

Ok you must just nag me as I am so overloaded at work it isnt funny!