# Are glass canopies really that bad for gas exchange?



## Virto (Dec 6, 2012)

Most gas exchange is brought on by the movement of water - your filter handles that if it's a hang on back, but if you have a canister, you can point your spraybar up to break the water. You shouldn't run into any real issues with a canopy - they aren't air-tight. They will cut down on evaporation, which is a good thing.

Cories are nuts - people don't think of them as jumpers, but my emeralds sure do.


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## kman (Dec 11, 2013)

Agreed, there should be plenty of gas exchange even with a cover, as long as it's not an airtight seal.


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## deconstructionalism (Jan 30, 2015)

Thanks for the responses guys! Yeah, my albino corys pop up quite often and every now and then they actually leave the water.

Do you think I may need circulation beyond the power filter to equilibrate gas levels throughout the water? I was thinking of one or two powerheads. Is that even necessary?


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## kman (Dec 11, 2013)

55 Gal with an HOB is probably fine, but you should be able to tell by watching your plants, and seeing if they're getting enough flow. If they're healthy and happy, it's probably fine. Else a powerhead shooting across the front would probably be helpful. I doubt you'd need two.


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## deconstructionalism (Jan 30, 2015)

Thanks again. I guess I have one last elephant in the room question. Am I being a complete moron trying to set up a planted tank with a common Pleco? I was thinking about potting plants and just having carpet plants that I don't care as much if they get uprooted or chewed. Any advice?


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## aquarium hippy (Feb 7, 2013)

imo a common pleco will get too large eventually for a 55 anyway but he will most likely be hell on your plants. but I have never personally tried it.


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## PlantedRich (Jul 21, 2010)

The pleco question is like a lot of other things we deal with in the hobby. As he gets bigger, he may do more damage-- or not. Tons of things that change the answer. Feed him some veggies like zucchini and he may never develop a love of plant leaves?
But it won't be something that suddenly comes round but slowly grows. At that point, it will be decision time. Do you want it bad enough to pay the price? He may rasp on leaves and you begin to see thin spots. Normal and to be expected. 
Glass covers are not so tight that they are a problem. Especially with a HOB filter taking water out of the tank and passing it through the air going back into the tank.


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## Maechael (Sep 9, 2012)

I have a 55 community with angels, cories and tetras with a common pleco in it, dual HOBs and plexiglass tops. My cories rarely break surface but they do shoot to the top almost hourly.


The type of plants being considered is important, as is a piece of wood for the pleco to rasp on, I suggest malaysian as it seems to sit well in most tanks.

Large pleco v small sword, barely any sword left.
large pleco v any kind of small carpet, one solid swish and it's uprooted.

Rotala seems to stay planted farily well, as do my anubias and my larger crypts.
all of my swords have been rasped, the largest to shreds the smaller to stalks with a root.


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## deconstructionalism (Jan 30, 2015)

I think I may do a Pleco tank in the front den hallway (55-80 gallons) with some cleaner fish and only floating plants..We'll see how that works!


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