Open Top Tanks

[lyotim88]

do you think open top tanks are "healthier" because you have to top-off more?

 

[PRW1988]

Personally I found that the water evaporated quicker with the top off than on. Though I did have a MH system, which could've been why.

 

[SkiFletch]

do you think open top tanks are "healthier" because you have to top-off more?

Yes, but not for that reason.

Open topped tanks are healthier because they allow for more gas exchange which means more Oxygen and less CO2. Seawater does NOT hold O2 as well as freshwater (all the salt in the water takes up all the "room" O2 could usually take) and thus gas exchange at the surface is much more important for a successful tank.

 

[ben1987]

you dont gain anything from topping up really often, its just near RO water you use to top up, all the elements are added to the water via the salt mixes we use.

It is essential for a stable tank to keep the SG around the same by topping regular up though.

 

[xxBarneyxx]

As ski said you get better gas exhange with an open top tank, also in a hot climate it can help to cool the tank down and keep the temp more stable (through water evaporation).

The downside is the evaporation which will be increased in an open top tank (espeically when its hot) and you also need to make sure that you have some kind of cover on it as a lot of marine fish are pretty jumpy.

So yeah if you have an auto top up unit or regularly top up the water then I would say an open top system will be more healthy (or at least has some good advantages to it over a closed lid system).

 

[Siamese Fighter05]

One thing that i might add which can be increased through an open-top tank is surface scum so try and make sure you've got a decent amount of surface agitation to try and counter this problem, this will also help increase gas exchange allowing me 02 into the water

 

[lyotim88]

thanks for the replies. The real reason i want open top is to maintain the strength of the light(so it doesn't get weaker going through glass)

 

[ben1987]

if you using halides heat isnt anywhere near as much of an issue open topped compared to trying to box them in