[Ajmags13]

Well I have a few questions.

In relation to oxygen levels does a protien skimmer keep a good amount of oxygen in the water ?

I keep my tanks at 81.5 degrees and I keep the surface of the water moviing at a pretty good clip. This helps with the oxygen but sometimes in the summer months, even though the AC is on, it can get hot in the tank with temps as high as 85 or 86 ( think in all my years keeping fish I have only seen one of my tanks reach 85.5 once). Is the oxygen level the only thing that effects fish at high temps ? Or do the fish simply not like the higher temps? Are the higher temps causing other problems for fish other than the obvious oxygen problem?

[leebca]

I moved your post into its own thread to get it out of that very old thread.

What is most important is gas exchange. Gas will exchange with dissolved gases depending the mix of gas around the aquarium. If you keep the marine system in a closed room high in carbon dioxide and low in oxygen, then that will be reflected in the aquarium water.

The skimmer and water movement affects the amount and speed of gas exchange. To provide the highest oxygen content in the water, you want the highest oxygen content in the air around the system.

Fish kept at high temperatures have an increased metabolic rate. Although the quantity of dissolved gases goes down at higher temperatures, the quantity of gas between 75 and 85 isn't that great. BUT combine this with an increase in metabolic rate and the fish can be stressed.

At high temperatures and low temperatures, the physiology (internal chemistry) of the fish can change. At low the chemistry can slow down; at high temps the chemistry may not function as it should. Each fish is its own chemical factory which in part depends upon temperature.

[pearl_aqg]

Are your fishes showing signs of stress at the higher temperatures? The increase in metabolism is stressful on the system, but the main thing with temperature, like a lot of water conditions, is that it doesn't change too rapidly. Your fishes can probably handle warmer temps in the summer even if it's not ideal for their biological processes, as long as they get slowly adjusted to the warmth and then back to the cooler temperatures.

It sounds like your fishes made it safely through the temperature changes of the summer? You might be ok without adding a chiller...you can always try to help by shading them from indirect sunlight from windows, or if the heat rises more than you'd like, dropping in a ziploc baggie with ice inside to cool things down a little.