What's with the trend for 'Open' tanks?

[robmcd]

All of my tanks are lidless, but I do have a hood on my 120 gal. I prefer to go without lids as all of my tanks are planted and I want the plants to get the full strength of the lighting. I have found that with the hard water that I have in my area, the lids get calcified quicker and it tends to diffuse the light. I get a fair amount of evaporation, but my tanks get 50% WCs a week so it's basically all cyclical. Also, all of my tanks get topped off to the midway part of the upper trim.

 

[Byron]

Any water added to a freshwater fish aquarium should always have parameters that are basically the same as the tank water. This applies to water changes or topping up. Agreed that adding a pint of water to "top up" is not going to make much difference, but if this is being done day after day it can. A stable biological system means the parameters are stable, not fluctuating; this includes the GH, KH and pH.

Topping up should not be necessary to begin with. Even in the hottest days (day temperature high 30's, almost 40 C) we had this summer, lasting for a week or longer, none of my tanks needed this.

 

[Deleted member 149562]

If you really want that naked aquarium you can always buy mesh kits....like this....

Universal Aquarium Mesh Covers | Kraken Corals

Keep your fish from accidently jumping out of your reef tank with a mesh aquarium cover, cut to size and easy to install a must for any modern reef tank.

krakencorals.co.uk

Or you can use a clear plastic condensation cover....like this....

Condensation Covers - Aquarium Accessories & Products | AquariumH2o

Condensation covers or trays provide a physical barrier between the aquarium water and the electrical fittings in the tank hood in aquariums & fish tanks.

www.aquariumh2o.com

You cannot see them when viewing the aquarium until you look from above. Both options keep flotsam out and the beasties in.

 

[Deleted member 149562]

BTW...the mesh kits can be used on freshwater as well as marine.....widely available online and in many LFS. Not overly expensive, the clear plastic condensation covers are cheaper and can be cut to fit around filter pipes etc with ordinary scissors. Mesh kits can also be adapted to fit around any obstruction too.

 

[Myraan]

Any water added to a freshwater fish aquarium should always have parameters that are basically the same as the tank water. This applies to water changes or topping up. Agreed that adding a pint of water to "top up" is not going to make much difference, but if this is being done day after day it can. A stable biological system means the parameters are stable, not fluctuating; this includes the GH, KH and pH.

Topping up should not be necessary to begin with. Even in the hottest days (day temperature high 30's, almost 40 C) we had this summer, lasting for a week or longer, none of my tanks needed this.

Not that my tank is lidless, but I've been going by the theory that if you have to top up in between water changes, you are not changing water often enough. And if the amount you top up "by accident" during a regular water change is enough to alter parameters over time, the amount of water you are changing each time is too small.

Are my assumptions correct?

I used to read about "old tank syndrome", but that was in the days that 100ppm nitrate was considered fine, as a result people with plants would frequently never change water. I read about anecdotes where people would inherit a grandparent's aquarium that had lost 50% due to evaporation with a thriving population of fish (I would assume allbeit with a reduced lifespan, so technically not thriving)

 

[Byron]

Not that my tank is lidless, but I've been going by the theory that if you have to top up in between water changes, you are not changing water often enough. And if the amount you top up "by accident" during a regular water change is enough to alter parameters over time, the amount of water you are changing each time is too small.

Are my assumptions correct?

Yes. There could of course be other factors (undesirable) causing fluctuations in parameters, but above is certainly one.

I used to read about "old tank syndrome", but that was in the days that 100ppm nitrate was considered fine, as a result people with plants would frequently never change water. I read about anecdotes where people would inherit a grandparent's aquarium that had lost 50% due to evaporation with a thriving population of fish (I would assume allbeit with a reduced lifespan, so technically not thriving)

Likewise. One wonders how the poor fish survived, but admittedly back then most did not overstock like the tendency is today, and the plants did a huge benefit.

Nitrate being mentioned, this is another test that should never fluctuate for years. My tanks have all registered in the 0 to 5 ppm range every time I tested nitrate, over the past 12 years. I no longer do, it is obvious there is biological stability; if nitrates go up between water changes, the W/C are not sufficient either in volume or frequency or both, or the tank is overstocked/overfed, etc.. The pH also never varies more than a couple decimal points in any of my tanks over 12 years.

 

[PheonixKingZ]

Is there not a danger of messing up your water hardness and therefore PH by adding RO water with no buffering? Over time there is maybe potential to drop your PH buffer capacity enough that you will start getting wild PH swings.

I could be wrong (it happens often) but in my head:
You have a tank with tap water around say 6KH. You top up with RO water and that maybe drops it to 5.8KH. You then do a water change with tap water and that brings you buffer back up a bit but maybe not right back to 6KH. Over time your KH drops a little bit each time you top up and then eventually gets to a point where your PH can start bouncing about.

A SW tank isn't bothered by this because it has a lot more stuff to act as a buffer but I believe (and again I could be wrong) that in a FW tank it's not quite the same.

I know in the past when breeding softwater fish I have managed to drop KH and then PH quite rapidly with just small amounts of RO so not sure I would want to put it directly into my tank.

This is a very good point. My hardness does seem to stay the same, as I’m doing weekly water changes.

I will definitely keep my eye out for this!

 

[Mikeyboy123]

I thought I was a fish down since doing a water change on Saturday. Just found it on the floor covered in fluff and dried out. I have a glass cover on my nano but took it off to do the water change and it must have made a bid for freedom or was perhaps startled by something. Gutted, but also reassured that the loss of a fish was not due to disease or problems with the water. will be more careful next time. Always have a cover!

 

[Myraan]

Water change day is terrifying if you have hatchets, they basically fly like some kind of insect.

 

[dasaltemelosguy]

I love emergent plant tanks. The nitrate reduction can be astounding (particularly with the 'Lucky Bamboo')...and I think they can be beautiful!

That said, in the past I've found my best Yellowheaded Jawfish and Electric Blue Hap on the floor on two different mornings so I no longer dare risk it.

Instead I used lighting grid from Lowes which passes almost all light (by design) and is waterproof and rigid and may be cut to exactly replace the glass panes on most covers. For me it's the closest to open top without the risk. It also cost $10 to completely cover a 6', 125G. I use it to support dracaena (Lucky Bamboo) and pothos:

 

[Mikeyboy123]

Water change day is terrifying if you have hatchets, they basically fly like some kind of insect.

Yeah, I’ve been there with marbled hatchets, another candidate fish for the what fish do you regret buying thread! I used to have an old style hood with fluorescent tubes and used a corrugated condensation tray underneath. I cut a 1 square centimetre hole in the condensation tray to introduce food, no other gaps or holes anywhere. You bet, one day I lifted up the hood and found a dead glow light tetra on top of the condensation tray.

 

[Mikeyboy123]

I love emergent plant tanks. The nitrate reduction can be astounding (particularly with the 'Lucky Bamboo')...and I think they can be beautiful!

That said, in the past I've found my best Yellowheaded Jawfish and Electric Blue Hap on the floor on two different mornings so I no longer dare risk it.

Instead I used lighting grid from Lowes which passes almost all light (by design) and is waterproof and rigid and may be cut to exactly replace the glass panes on most covers. For me it's the closest to open top without the risk. It also cost $10 to completely cover a 6', 125G. I use it to support dracaena (Lucky Bamboo) and pothos:

View attachment 145793

View attachment 145794
View attachment 145795
View attachment 145796

I like the look of them, especially with plants growing out, but I just think they aren’t really practical. Too much risk of things getting in and out of the tank.

 

[Happilyretired]

From my experience of aquariums in the late 60s, the 70s and 80s, tank lids were always, ALWAYS, considered to be essential, especially for tropical tanks.
Not only did the lid hold the lighting, be it bulbs or fluorescent tubes, but it helped reduce evaporation, minimised fish loss through jumping and, perhaps most importantly, it stopped dust and household airborne contaminants reaching the water surface.

Today, I see this popular trend for open tanks and, whilst I can appreciate the aesthetics of such a tank, I'm wondering about jumping fish and those aforementioned 'airborne contaminants'?
The increased emphasis on plants is, as far as I'm concerned, a Good Thing and I do like those tanks with the plants growing up and out of the water.
I can also appreciate the nice lighting now available and the ability to get that 'different' view of the tank from above...although I suspect that might freak the fish out somewhat, as a potential predator suddenly appears above, casting its predatory shadow.
Another factor with the light would be an actual reduction in the control of the light spectrum entering the tank. With a lid and modern lighting, the majority of the lighting can be controlled, with ambient lighting only entering from the sides left clear. Without a lid, ambient lighting enters from all five sides.
I can also appreciate the visual impact of a clear glass box, with colourful movement inside it, with visible frames and equipment kept to a visual minimum, although, again, I question the effect of such an open arrangement on the well-being of the fish.

Do those of you who have such tanks use a glass cover and, if not, how do you stop your fish jumping ship, minimise evaporation and stop airborne contaminants?

I have a cat, actually 3, and one is only a year old so he is still easily excited by toes, fingers, dogs tails, and my tank. So, I keep the lid on and secured, but even without my kitty, Joe Biden, I’d keep the lid on it

 

[WhistlingBadger]

Emergent plants are the only reason I can see for a lidless tank, personally. I have holes cut in my Sumatra tank for rice to grow up through (hopefully, someday, maybe), but the evaporation is annoying.

 

[Mikeyboy123]

Found another chilli rasbora on the floor this morning. The glass tank cover is probably 2 cm smaller than the tank front to back and I usually have it as forward as it can be unless I'm introducing food, which leaves probably a 5mm gap at the front. Must have forgot to move it forward again after feeding last night and one has jumped out. So annoying, they are thriving otherwise. I've got a sheet of perspex and am going to cut it to exact size.