Acrylic/plexiglass cover to control evaporation

[PaulE61]

Hi
Anyone covered their tank with plexiglass to limit evaporation?, will affect my params if I do?, its causing excess condensation in my home leading to mould, Manchester UK atm is cold damp and 5 degrees C today, opening the windows beyond a bit of ventilation is not an option.

 

[Randy Holmes-Farley Verified Community Expert]

While it may be needed for mold and such, a cover does reduce aeration and is not optimal, IMO.

 

[penguinexdeus]

Hi
Anyone covered their tank with plexiglass to limit evaporation?, will affect my params if I do?, its causing excess condensation in my home leading to mould, Manchester UK atm is cold damp and 5 degrees C today, opening the windows beyond a bit of ventilation is not an option.

it may limit gas exchage, so you probably don't want to fully cover. Some custom cover manufactuers have covers for the net portions that can be put on/ off. i have one on a nano tank, but the the AIO back portion remains uncovered for gas exchange. The additional acrylic and condensation on the acrylic does reduce par from lighting as well and you can grow algae/mold on the lid also so need to clean it periodically.

 

[Gill the 3rd]

I used those clear polycarbonate sheets used for greenhouses. I didn't have any gas exchange issues (at least I don't think I did and didn't notice any issues), but I was getting a lot condensation on the covers. I had to constantly wipe it down and they messed with my par levels as the covers got dirty. Ended up just using mesh covers.

 

[Randy Holmes-Farley Verified Community Expert]

I used those clear polycarbonate sheets used for greenhouses. I didn't have any gas exchange issues (at least I don't think I did and didn't notice any issues), but I was getting a lot condensation on the covers. I had to constantly wipe it down and they messed with my par levels as the covers got dirty. Ended up just using mesh covers.

Most folks do not measure O2 to know.

A skimmer certainly also helps aerate, but also adds it own moisture to the air unless you vent it outside.

 

[Gill the 3rd]

Most folks do not measure O2 to know.

A skimmer certainly also helps aerate, but also adds it own moisture to the air unless you vent it outside.

Yea I have a 75 gallon sump and separate 20 gallon refugium located in my large open basement with no covers, with a protein skimmer. I think I am getting a lot of air exchange through those since they aren't in a humid cabinet under the tank.

 

[fishyjoes]

I have a 20 gallon display and 10 gallon sump, both covered with "twinwall" poly-carbonate. I get evaporation of around 300ml per day. I haven't noticed any lack of aeration. I have a skimmer and there are a few openings in the cover for wires and plumbing.
I experimented with leaving the cover off my sump for a few days to see how much evap I would get and it was something like 1200ml per day or so.

 

[TX_REEF]

Have you considered a dehumidifier for the room in question? Just a thought.

 

[exnisstech]

Nothing wrong with covers to reduce evaporation if you have enough other forms of air exchange I suppose.
I took my covers off all of my tanks years ago. They were always covered in condensation and salt creep was terrible.
I run a dehumidifier in the basement where I have a 125g as a sump connected to my 180g DT on the first floor. I also have two other tanks on the first floor. I have no idea what my total evaporation rate is but I dose 7300 ml of kalk daily in the basement sump and that is less than my evaporation rate for that tank. The other two I just fill the ATO containers when they need I don't worry about the evaporation as it really doesn't seem to be a problem in our home.

EDIT : I tried 1/4inch plexiglass before and it sagged terribly after a while. It may work on a small enough tank.

 

[fishyjoes]

EDIT : I tried 1/4inch plexiglass before and it sagged terribly after a while. It may work on a small enough tank.

I tried it on a standard 10 gallon (20 inch) and it still would sag after a few days

 

[SteveMM62Reef]

I have Glass covers over all of my Aquariums, haven’t had a problem with gas exchange on any of them. My pH would change when they are on and off the Aquarium. This is on two Sump systems, one modified AIO, with a glass top, and a ABS Top over the back chamber only during the Winter. Also my 30 Gallon Quarantine with HOB Filter(s). If you go with Acrylic, make it so you can flip the top, as it will warp. I personally prefer Glass with the hinge and back Strips. All glass from a local glass shop.

 

[Cell]

My basement tanks get covered with Lexan sheets during the MN winters.

 

[Randy Holmes-Farley Verified Community Expert]

I have Glass covers over all of my Aquariums, haven’t had a problem with gas exchange on any of them. My pH would change when they are on and off the Aquarium.

Trying to understand that last sentence.

Does it mean the pH changes day to night regardless of whether there was a top or not

or

Does it mean there was a difference in pH with a top compared to the pH without the top on the tank?

 

[PaulE61]

Have you considered a dehumidifier for the room in question? Just a thought.

Hi
I have 2 de-humidifiers running, in other rooms, I live in a single floor Flat/apartment only 64 square metres but I suspect they are adding to the issue as they are used for drying rooms I seem to be emptying them more since I set up the tank, back to square one, think the tank is the issue.

 

[Poseidon03]

Hi
I have 2 de-humidifiers running, in other rooms, I live in a single floor Flat/apartment only 64 square metres but I suspect they are adding to the issue as they are used for drying rooms I seem to be emptying them more since I set up the tank, back to square one, think the tank is the issue.

How many of gallons do you use to top of your tank per week?

How many gallons of dehumidifier do you dump per week?

 

[PaulE61]

How many of gallons do you use to top of your tank per week?

How many gallons of dehumidifier do you dump per week?

 

[SteveMM62Reef]

Trying to understand that last sentence.

Does it mean the pH changes day to night regardless of whether there was a top or not

or

Does it mean there was a difference in pH with a top compared to the pH without the top on the tank?

No difference with the top/covers on or off. My 65 Gallons uses outside air, as it’s an older aquarium, and can have pH drops due to varying CO2 levels in the house. The 120 Gallon and Oceanic are newer aquariums, with newer mix of Sand and Gravels, which I believe contributes to higher pH. Remember, that a top does not hermetically seal an aquarium, there are many openings left.

 

[TokenReefer]

drying rooms

Whats this? I live in a small space and a dehumidifier can dial in to whatever % humidity you'd prefer...

 

[Randy Holmes-Farley Verified Community Expert]

No difference with the top/covers on or off. My 65 Gallons uses outside air, as it’s an older aquarium, and can have pH drops due to varying CO2 levels in the house. The 120 Gallon and Oceanic are newer aquariums, with newer mix of Sand and Gravels, which I believe contributes to higher pH. Remember, that a top does not hermetically seal an aquarium, there are many openings left.

OK, I understand what you are saying. I think it would be useful to see O2 in tanks with a top vs no, however. I don't see how a lid can selectively allow O2 and CO2 to freely pass, and not water.

 

[PaulE61]

How many of gallons do you use to top of your tank per week?

How many gallons of dehumidifier do you dump per week?

I knew someone ask that, Lol
I have a waterbox 60.2, I use about 8-9 litres RO a week, but to be honest I really need to accurately measure the evaporation
one Dehumidifier holds 2.5 litres, I used to empty it once a week, now about every three days
the other holds 3.5 litres and again about every three days
I've had the smaller one running for years as we are prone to excess condensation, got a another due to increased condensation after tank setup.