My first aquarium (picture)

I agree...da big rock is a little outta scale...several various sized rocks will add more interest....
 
It doesn't look like your HOB is pumping good. Hard to tell by the pic, but could you check it for me!?!? That is the heart of your system. Without that, it would be daily 50% water changes. Also, that is like a septic system.

Good looking tank, tho. I love the colour of your gravel.

Daniel
 
I do too.

Yeah, but you have to think it is probably cutting the total volume of water in the tank down by half; thus, making it a more unstable environment. Not to mention it's their first aquarium.
 
Looking at that heater, it looks like a Penn plax right? I had one of those and it failed on me, it brought the temp up to 90 then dropped to 60, killing most my fish. I would at least get a backup one
 
I agree it's a cool rock! In my amateur opinion, it's probably fine, as long as you're vigilant about your levels and water quality, since it looks like you have a pretty light bio load. However, your fish might be happier with a little more open space for swimming. I'd switch it out for some smaller rocks, and save the big one for a bigger aquarium. Some living plants would also be great for the tank, for the look, for health, and for giving your fishies lots of hiding places.
 
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