Is There A Problem Or Rule With Filling Up A Tank Too Much?

[Osage_Winter]

I recently let my 60 gallon's water level drop to about 15% from natural evaporation, and then topped it off with conditioned (with Prime) fresh water, but I really filled the tank to the rim -- the water level is almost touching the glass versa tops that sit under the canopy. I have noticed that since then, my three fancy goldies have been looking for more air, seemingly, trying to get to the open back portion of the tank where there is no cover due to the filters hanging -- and last night I was very concerned because they began acting weird, like just floating around in the water without much energy and swimming strangely. I looked up that this could have been an oxygen issue in the water, so I am beginning to wonder if there's too much water filled too high in the tank -- is this possible? Do the fancytails in particular require more surface area for breathing and O2?

 

[sarahh]

i would say that you didn't think about the bio load in terms of reducing the poop in the gravel. the water change should start with a gravel vac. did you check your nitrates, nitrites and ammonia levels?
the tank does need movement across the surface of the water to allow gaseous exchange, so if there is no "open" water, the air could be an issue too. 3 fish is a pretty good stocking, so do make sure that you have adequate filtration and clean the filter and gravel monthly at a minimum.

also, salts and minerals do not evaporate, so you may have too many salts and minerals in the tank.
JMO

 

[Osage_Winter]

i would say that you didn't think about the bio load in terms of reducing the poop in the gravel. the water change should start with a gravel vac. did you check your nitrates, nitrites and ammonia levels?

But I'm talking more about how they are now kind of acting weird and swimming weird, notably since I filled the tank to almost beyond the brim...

the tank does need movement across the surface of the water to allow gaseous exchange, so if there is no "open" water, the air could be an issue too. 3 fish is a pretty good stocking, so do make sure that you have adequate filtration and clean the filter and gravel monthly at a minimum.

There is PLENTY of movement and current across the water surface from an AquaClear 110 and Aqueon QuietFlow 55 PLUS two bubble wands that create enormous amounts of bubbles -- so, the current movement and filtration isn't a problem right now. It's the amount of "open water" as you put it; is it better, I guess is what I'm asking, if a tank isn't filled RIGHT to the top of the glass covers/hoods?

also, salts and minerals do not evaporate, so you may have too many salts and minerals in the tank.
JMO

But this behavior with the three goldfish just began since I filled the water level to the very very top...

 

[sarahh]

ok .
stresses fish will act/ swim weird. Nitrates, nitrites and ammonia in excessive levels will stress a fish

filling the tank to the brim is a bad idea whichever way you look at it.

if you have water with minerals and salts in in, and the water evaporates, it will leave salts and minerals. If you then add the same water with the same levels of salts and minerals, you will then have EXCESSIVE salts and minerals.. get what i mean?

 

[Osage_Winter]

ok .
stresses fish will act/ swim weird. Nitrates, nitrites and ammonia in excessive levels will stress a fish

Got this...

But again, this literally began as soon as I filled the tank up to capacity...

filling the tank to the brim is a bad idea whichever way you look at it.

This is actually the first I am hearing about this in such a passionate, definitive slant -- is this true for tropicals/salt water-marine as well as coldwater/goldfish species? I was told that it really doesn't matter how far a tank is filled, and that by filling to a brim, it actually quiets the return flow of the water from the HOBs...which I already knew, but my point is, no one ever told me this wasn't good for the fish...

Can anyone else confirm this?

if you have water with minerals and salts in in, and the water evaporates, it will leave salts and minerals. If you then add the same water with the same levels of salts and minerals, you will then have EXCESSIVE salts and minerals.. get what i mean?

Yes, I see what you mean. Thank you.

 

[libbyb]

When was the last time you did a PWC? You mentioned that you added water after it evaporated but that isn't the same as an actual PWC. And a good vacuum.

 

[Osage_Winter]

When was the last time you did a PWC?

Too long ago...

You mentioned that you added water after it evaporated but that isn't the same as an actual PWC. And a good vacuum.

Indeed; I am discovering that the hard way I think...

 

[libbyb]

That might be the problem, then.
If you want to go longer between PWC's, I wouldn't go more than 2 1/2 to 3 weeks MAX. You have goldies so you might need to do it more often due to their bioload. And you have to do it gradually. Then you have to be regular about it. It has to be routine.
Also, I wouldn't fill the tank to the brim. Maybe it's just habit but, I like to have about an 1 1/2 to 2 inches from the top. I'll fill my tank to the bottom of the frame. Even with an air stone, you need as much oxygen getting into the water as possible.

 

[sarahh]

This is actually the first I am hearing about this in such a passionate, definitive slant -- is this true for tropicals/salt water-marine as well as coldwater/goldfish species? I was told that it really doesn't matter how far a tank is filled, and that by filling to a brim, it actually quiets the return flow of the water from the HOBs...which I already knew, but my point is, no one ever told me this wasn't good for the fish...

just more splashing, fish are closer to the top and they can jump out. i have vigorous feeders, and i end up with water all over the carpet if i am not quick.
i had a fish dive out of a hole made for a heater. a 4 inch adult jewel cichlid through a tiny hole... they can be crafty. so i don't recommend helping them escape

 

[Osage_Winter]

I wouldn't fill the tank to the brim. Maybe it's just habit but, I like to have about an 1 1/2 to 2 inches from the top. I'll fill my tank to the bottom of the frame. Even with an air stone, you need as much oxygen getting into the water as possible.

Then I suppose this is the answer to the thread's initial inquiry; thanks.

I'll have to just let this batch evaporate then and go back to not filling all the way up...

 

[Osage_Winter]

just more splashing, fish are closer to the top and they can jump out. i have vigorous feeders, and i end up with water all over the carpet if i am not quick.
i had a fish dive out of a hole made for a heater. a 4 inch adult jewel cichlid through a tiny hole... they can be crafty. so i don't recommend helping them escape

LOL -- well I always close both my glass tops and the wood canopy after I drop the food in, so there's no way these guys could escape...

 

[MarkA123]

This is probably true, I never fill mine up to the top anyway because of all my labryinth fish, ADF's, Betta, and corys.

Got this...

But again, this literally began as soon as I filled the tank up to capacity...



This is actually the first I am hearing about this in such a passionate, definitive slant -- is this true for tropicals/salt water-marine as well as coldwater/goldfish species? I was told that it really doesn't matter how far a tank is filled, and that by filling to a brim, it actually quiets the return flow of the water from the HOBs...which I already knew, but my point is, no one ever told me this wasn't good for the fish...

Can anyone else confirm this?



Yes, I see what you mean. Thank you.

 

[Osage_Winter]

This is probably true, I never fill mine up to the top anyway because of all my labryinth fish, ADF's, Betta, and corys.

Thanks Mark,

So you're basically agreeing that a tank shouldn't be filled right to the edge of the glass tops/canopies/hoods?

 

[Mark Hewitt]

It doesn't matter how much you fill it as long as there is air above the surface. Either with an open back to the hood or supplied by an air pump.

 

[BigJim]

I fill my tanks all the way to the glass canopies in an effort to conserve CO2 for my plants. The HOBs and the plants do an adequate job of oxygenating the water. I've never seen my fish gasping at the top and I've got some stuffed tanks.

 

[MarkA123]

Yes, especially if you have labyrinth fish

Thanks Mark,

So you're basically agreeing that a tank shouldn't be filled right to the edge of the glass tops/canopies/hoods?

 

[Osage_Winter]

There are some conflicting reports here, lads...is it safe to fill a tank to the glass tops/hoods (to the brim, essentially) or is this bad to do?

 

[fort384]

I agree that the level of the water is not important. What is important is that there is room above the water's surface for gas exchange to occur. If the hood is almost touching the water, this can't happen. I have no lid on my tank I am currently running, and I fill it to the point that it is almost overflowing. I mean like surface tension is keeping the water from spilling over the top. And I top it off daily (and do PWCs weekly, to make sure fertilizer levels remain good, and to make sure I am removing ions/metals/particulate along with keeping the tank full from evaporation. )

 

[BillD]

I like to fill my tanks to the top. Nothing looks much worse than seeing the water level below the trim. The only thing that could be causing a lack of oxygen is too tight fitting glass tops. Air stones don't add oxygen (no meaningful amount) to the water directly, but cause a current to allow gas exchange at the surface.

 

[Osage_Winter]

Well, I'm not sure which road I am going to go down...right now, the water is right below the glass versa tops (2 24" ones by Aqueon) and the waterline is actually touching the glass center brace, causing massive walls of bubbles to form under there; probably harmless, but it's going to take awhile for the evaporation to return...

I just didn't want the fish to be suffocating in some way from doing this...