Water doesn't seem to be affected by evaporation

[kira76]

Hi, I'm currently running a 3ft x 2ft x 2ft tank with sump. The tank have been running for about 6 weeks but the funny thing is, I don't see a massive drop in the water level that requires me to top up the water like what I've read in the forum.

I've check the SG at least once per week and it's constantly at 1.020~21. I've done weekly waterchange of at least 10% and am running the tank with 6 tube T5HO and a 1/4hp chiller set at 25~26 degrees.

While there are some water lost due to evaporation, it's minimum and doesn't seem to affect the SG. Is this normal? Especially so with the recent hot spells.

[tunicate]

There will be substantial evaporation unless your environment is very cold & damp.

Otherwise, you're probably adding in more water than you take out during WC to compensate for the amount evaporated.

[dnsfpl]

measured using hydro or refractor meter?

[kira76]

There will be substantial evaporation unless your environment is very cold & damp.

Otherwise, you're probably adding in more water than you take out during WC to compensate for the amount evaporated.

That's the problem. There are some evaporation. But not what I've read in forums or discussion with others where I need to add in more than 1 liter or water per week. I don't seem to have to do that, for now. Previously, when I'm keeping aro without chiller in a 5 feet tank with only 1 tube of T8, the evaporation was like about 1 liter every 2 to 3 days. I'm wondering if it is due to the fact that I'm running a chiller.

measured using hydro or refractor meter?

Measured using refractor meter.

[sun2000]

T Previously, when I'm keeping aro without chiller in a 5 feet tank with only 1 tube of T8, the evaporation was like about 1 liter every 2 to 3 days. I'm wondering if it is due to the fact that I'm running a chiller.

If you use chiller the evaporation is much lower , if you have a fan it will be worse..

[dnsfpl]

yes is much lower but 6 weeks never topup?

easily 10l of water

[tunicate]

There are other factors contributing to rate of evaporation.

(1) Higher water circulation causes higher evaporation.(Adding wavemakers & changing to a more powerful return pump)

(2) An overflow system encourage water movement on the tank surface, also adds to evaporation.

[sun2000]

yes is much lower but 6 weeks never topup?

easily 10l of water

I think 6 weeks no top up is also quite strange but I think TS did top up ...

"I don't see a massive drop in the water level that requires me to top up the water like what I've read in the forum.

I've check the SG at least once per week and it's constantly at 1.020~21. I've done weekly waterchange of at least 10% and am running the tank with 6 tube T5HO and a 1/4hp chiller set at 25~26 degrees.

While there are some water lost due to evaporation, it's minimum "

only not as much until 1l per day but when I ran a tank with no chiller using a fan as cooling, I remember topping up 1.5L per day due to evaporation...bought a RO/DI unit to make top up water but when I added a chiller ( same tank) then top up amount was perhaps down to once a week 2L at most.. so I think the fan plays a part as well as maybe cooler water needs more heat to make it evaporate off from the tank.

That is what I observed..could be other reasons as well..

[RockyBoy]

It's ok if there is minimal evaporation, as long as the water parameters are alrite.

[kira76]

Thanks all, Ya, as highlighted, I do top up the water, it's just not as much as what I've read in the forum, only minimum top up.