Faucet question

good to hear. hopefully the little troopers will live long and fruitful lives.

sorry, micha. hopefully some of this conversation can be useful... or better yet you find a solution to your fluctuations... maybe you can find a spigot closer to the hot water heater so you don't get as much temperature creep.
 
I've found that filling with warmer water tends to be safer than filling with cooler water. Where I work, when we water change tanks, the tanks range from 78-74 degrees depending on which row the tanks are on. I tried filling at 76, and I noticed the top tanks started to get ick more often, sensitive species started dying occasionally after water changes and occasionally tanks would crash where all the fish or all of a single species of fish in the tank would be dying.

Afterwards, my boss told me to always fill warm. Now that I fill at 78-79 the top rows stopped having these problems anymore than the bottom and middle rows do (which is not often at all).

Maybe the cooler/warmer water rule applies differently to fish when they are stressed or in fish store settings and when they are settled into their new home tank.
 
I use a thermostatic mixing valve when filling my tanks. Having discus only, I refill my tanks with 84-85 degree water from the tap. It may be an overkill if you are just filling 1 tank but I fill between 200-300 gallons a day and without it, my water temp fluctuate too much if.

1. someone flush the toilet
2. washing maching running
3. someone taking a shower
4. Hot water isn't as hot as the tank are filled.

Over a 2 hour period, one of the above will happen.
 
I'm assuming your tap temp increases as you're filling? Mine does this. Depending on the size of the house, distance water has to travel from the heater to the tap and age of the faucet it can sometimes take several minutes for the water temp to stabilize at the tap. What I do is to let the water from the tap be a little cooler than the tank, then check the temp after about 5 minites. Usually it has risen a couple degrees to the tank temp.

Remember also, the second you turn on a hot water valve, cold water begins entering the water heater tank. Depending on the temp of the holding tank, the size of the holding tank and the temp of the cold water entering the tank, the temp of hot water at the faucet can begin to fall soon after filling.

The fix here may be that you have to keep checking during filling and adjusting the faucet valves.

Mark
 
Oooh. A thermostatic mixing valve... Sounds pricey. I have to look into this.

Right now I have 7 aquariums. I think getting a thermostatic mixing valve would be worth it.
 
Maybe I've missed something, but why not just refill the tank slowly with cold water so that the aquarium heater(s) can maintain the temperature within a couple of degrees of their set temp?
 
Oooh. A thermostatic mixing valve... Sounds pricey. I have to look into this.

Right now I have 7 aquariums. I think getting a thermostatic mixing valve would be worth it.

FWIW, most thermostatic valve will be good for you only if you are filling 84+ degree temp. I know for the one I use, the min temp is somewhere around 80 degree.

I got my first one for about $60 but recently found a person selling on ebay for about $30
 
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