Evaporation and Water Movement

[Fresh2o]

I was wondering if there is a correlation between surface water movement and evaporation. Specifically, can increased surface movement lead to increased evaporation?

Ever since I went topless about a month ago, I have noticed quite an increase of evaporation. This is a 20g long with an AC50 (well, I added a second one because I am seeding it for a new tank). The filters have an extension on the output to cut down on the splash and redirect to flow along the surface which the hope of increasing gas exchange. I think the trade off is water loss which makes sense. Here are some pics:

 

[armymp327]

i think it does, ever since i pointed my canisters spray bar output more towards the surface (i also have no top) ive noticed alot more evaporation,

 

[Phranque]

Absolutely..... With the combined factors of going open-top & increased surface aggitation, evaporation is going to increase dramatically.

Nice looking tank, BTW

 

[Fresh2o]

Thanks for the replies. I suspected this was the case but was looking for additional input on the matter.
Since this tank is not in a bedroom, I may take the "waterfall extensions" off and see how that affects the evaporation rate. Without them on, the output hits the water at about a 45 degree angle and sometimes causes gravel displacement. I had some cabomba at one time the the current was pounding them. I have Bacopa caroliniana it it's place now and it is not as frail. Also, I have some floating plants and I'll have to see how much they get tossed around. I suppose I could raise the water level a bit.

 

[Fresh2o]

Update: When I removed the filter extensions the current kept pushing the floating plants down into the tank where they get stuck on the moss or DW. I know I can "rope them off" to a section of the tank with fishing line but the current is also beating up on the Bacopa so i put the extensions back on.
Moving the filter over to one side might help. I'll give that a try as well as corralling the water lettuce. Yee-Haw!

 

[NYgiantsRP]

The water will deffenitly evaporate faster when there is more surface area for evaporation (movement) and when the lids are off. So the problem is the you don't want to have to top them off so often?

 

[Fresh2o]

The water will deffenitly evaporate faster when there is more surface area for evaporation (movement) and when the lids are off. So the problem is the you don't want to have to top them off so often?

The glass top when used with the light fixture (Finnex Fugeray) casts a blinding reflection and IMO a lot of light is lost (if it's lighting up the ceiling then it's not going in the tank). Now when I go on vacation or away for a long weekend, I'll put the glass top on to reduce evaporation while I'm gone.

 

[NYgiantsRP]

Oh ok. I see. I just put mine right on the glass, no reflection.

 

[Fresh2o]

Oh ok. I see. I just put mine right on the glass, no reflection.

My stock hood was fine (no reflection) but the Fugeray would reflect light. Plus the new fixture is so light compared to a fluorescent hood that when I lift the glass lid up, the fixture would slide back. I wanted to secure it with the legs that came with the fixture but found that the legs and glass top don't fit well together. My workaround is a pair of rails that I built and placed along the sides of the rim.

 

[BillD]

Try slowing the flow, or, removing one filter. Putting the lids on the filters will also help.

 

[Fresh2o]

Try slowing the flow, or, removing one filter. Putting the lids on the filters will also help.

The second filter is only in there temporarily. I'd rather not decrease the flow if possible. I used to run it with the lid but that seemed to amplify the filters noise. Anyone know of any mods to the lid to make it quieter?
I am going to try again with the filter in a different area (away from the Bacopa).

 

[armymp327]

you dont need to mod the lid, best thing to do with aquaclear filters is put some Vaseline or similar on the impeller shaft in the motor, this will make the aquaclear 99% silent, cotton swaps work good to apply the vaseline, and you may need to reapply vaseline every month or so, but thats when i take the filters out and do a good cleaning anyways

 

[Fresh2o]

you dont need to mod the lid, best thing to do with aquaclear filters is put some Vaseline or similar on the impeller shaft in the motor, this will make the aquaclear 99% silent, cotton swaps work good to apply the vaseline, and you may need to reapply vaseline every month or so, but thats when i take the filters out and do a good cleaning anyways

I placed the lid on the filter that ha been running for sometime an surprisingly it is pretty quiet. I guess the biofilm/slime build up has quieted things down. The other one is pretty new and I am going try the Vaseline later today.

I did modify the lip extensions to point downward. Not much splash and the number of plants that get dragged down with the current is minimal. I will keep an eye on the evaporation rate over the next few days and see if it changes.

 

[Bengals]

Glad to see somebody else had a similar problem after going topless. I'm interested in your adaptation to reduce splashing. Can you take a closer image or explain what you put there on the output. Looks like plastic of some kind. I've tried putting a bit of polyfil material that worked well but led to a bunch of floating white ugly bits in the tank as it detached.

I have less evaporation from our 20g long that has 2 sponge filters compared with the 29g that has an aquaclear 70 and aqueon 55. That needs a few gallons every few days unfortunately.

 

[DavidAl]

Do you have a ceiling fan in the same room as the tank or are the air conditioning vent pointed toward the tank? Those two things will help increase evaporation.

David

 

[armymp327]

Glad to see somebody else had a similar problem after going topless. I'm interested in your adaptation to reduce splashing. Can you take a closer image or explain what you put there on the output. Looks like plastic of some kind. I've tried putting a bit of polyfil material that worked well but led to a bunch of floating white ugly bits in the tank as it detached.

I have less evaporation from our 20g long that has 2 sponge filters compared with the 29g that has an aquaclear 70 and aqueon 55. That needs a few gallons every few days unfortunately.

instead of polyfil try using a filter sponge cut to fit in the output with the lid on

 

[Reygan2]

My stock hood was fine (no reflection) but the Fugeray would reflect light. Plus the new fixture is so light compared to a fluorescent hood that when I lift the glass lid up, the fixture would slide back. I wanted to secure it with the legs that came with the fixture but found that the legs and glass top don't fit well together. My workaround is a pair of rails that I built and placed along the sides of the rim.

Love the rails!! How did you attach them to the rim of the tank? I have the 36" Fugeray on my 40b and I'm topless too. I have the same issues, but I love the light.

 

[Fresh2o]

instead of polyfil try using a filter sponge cut to fit in the output with the lid on

An alternative for polyfill that comes in a large "pillow" is the type that comes in a sheet. Easier to cut and use from what I have read. Just make sure the product does not contain any chemicals.
I was using polyfill but switched to the blue/white Marineland brand that comes in a sheet/roll. The loose polyfill fibers ended up in the tank and I found some fibers wrapped around the filters impeller.

 

[armymp327]

An alternative for polyfill that comes in a large "pillow" is the type that comes in a sheet. Easier to cut and use from what I have read. Just make sure the product does not contain any chemicals.
I was using polyfill but switched to the blue/white Marineland brand that comes in a sheet/roll. The loose polyfill fibers ended up in the tank and I found some fibers wrapped around the filters impeller.

Your thinking of quilt batting, though I was suggesting filter sponge to help reduce output flow on the aqua clear filters. Not has filter media

 

[Fresh2o]

Love the rails!! How did you attach them to the rim of the tank? I have the 36" Fugeray on my 40b and I'm topless too. I have the same issues, but I love the light.

Superglue.
I had pictures of the rails in progress but due to a technical problem with my phone I lost the pics.
I used the type of PVC that is used as trim as an alternate to wood. I actually had some lying around because I was doing a project for a closet that required 3/4" x 1 1/2" wood trim. I was in a hurry so i selected the PVC since it required no priming and sanding. It is white and cuts easier then wood. I measured the width of the top of the existing rail and it's 1 cm. I ran the PVC trim through a table saw (I get better results with a table versus scroll or jigsaw) to get the 1cm width. The height is about 3/4". I trimmed off the corners to give it a finished look. I used a name brand black spray paint that is okay for plastic. After dry fitting I secured it with superglue.
Of note: I should have put on a third coat of paint before using. Or a final coat of varnish, lacquer, etc. After moving the light fixture once, it lifted off some of the paint. Not much but it was noticeable.
Here are some close up pictures: