I've heard talk of a technique called continuous water change here for some of the larger tanks. Can anyone shed some light on how this is done concerning keeping the salinity correct due to evaporation. How is this balanced? I think that this could be a great way to keep all the parameters in balance and much cheaper than all the additives that are out there ( two part this and that or messing with kalkwasser). It would cut down on test kits as well because you would always have a supply of perfect water coming into the tank.
The first thing I would do is determine the average amount of evaporation per day. I replace about 5 gal a day on my 240gal. I replace it by drip method in order to keep the sump water level constant. Before I change the water I make sure the water level is the same.
I assume what you mean by continuous water change you remove a certain amount of water and then at the same time replace it with new water. I really don't think this is practical nor that beneficial because you would also remove a certain amount of new water as well.
If I was this concerned about continuously new water I would change 15 to 20% of water a week, all the while keeping the evaporated water replenished.
You may already know this so forgive me if I didn'tn help any.
I am installing 3 65 gallon poly tanks downstairs. One for fresh RO/DI water, one for saltwater and one for waste water that will be used in washing machine. I am going to run this through a small controller to add and remove water from sump/tank and keep it at proper temp in saltwater reservoir. Will also use controller to keep water moving and aerated throughout the day. I thought that if water was removed from sump and added to tank there should be sufficient room for water not to be too well mixed if done simultaneously in small amounts. I could and very well may be wrong. It happens sometimes.
Install auto top off. Then use a set of timers and pumps and float switches, turn off auto top off turn on drain pump. Drain pump runs for a set amount of time. Then timer turns it off and turns on fresh saltwater pump. Pump fills until float switch turns it off then timer is redundant a few minutes later . Then auto top off turns back on.
One head takes SW water from the tank or sump to the house drain, another takes new SW from a mixing container to the tank. A float switch can be used to prevent the pump from draining the system if there is no new sw in the mixing container.
This system is independent from top off water system, which uses RO/DI water to replace water los through evaporation.
In my opinion, save your money, continuous water change systems are not worth the investment in time and money to set up and are just another point of failure. It's just as easy to draw off 5 gal, or how ever much you are going to change, and replace it with new water at the same temp and SG.
Continious Water Change
Linear Mode
