Heating & gravity of marine water

[SaltyDawg]

I bought a submersible heater trhee days ago that was 150watts for up to 50g or somthing like that.

I set the heater until the water warmed up to 80 degrees. ( the light was still on and I lowered it until it flicker and went off)

The temp dropped to 75 degrees the next day after I added the marine mix. ( oh yeah sorry, It is a 29 g tank)

I turned the heater back up and ever since it will not go any higher then 77-78 degrees with the heater at full open.

Is this or could this be , because the saltwater is denser? I know it is infact denser but I mean just in gerneral harder to keep a steady temp. with saltwater?

I had the same type of heater (before it broke that is), in the tank before the change over and all was fine with fresh water set up.)

Do you have to have a bigger heater with satwater then with fresh for the same amount of water to be heated and maintained at a constant temp?

Sorry if this seems to be a dumb question , but I'll be damn'ed if I know what the hell is going on with this thing?

It worked fine in the freshwater with the same tank.

Thank's in advance.

[Physh1]

That 150 watt heater should be ok for your tank. Usually you'd like 3-5 watts per gallon and a 30 would therefore require 90-150 watts.

 

What are you using for a thermometer? Internal or external? External thermometers tend to be affected by room temps, breezes, etc. You may be getting falso reading.

 

Good circulation around the heater helps distribute heat. If your room/apt/house is cold that will keep the tank from staying warm.

 

Water density really doesn't come into play enough to be a concern and have never heard of this causing issues.

 

Cameron

[SaltyDawg]

Thank you very much for the info. I am using an "El'Cheapo' stick on. I'll go out and buy an internal this weekend. Nothing is in the tank yet just sand so It's not critical yet.