Sump level goes low with my pump on

[jastonataquapro]

When I start my main pump (rated at 850Gph at 4ft in a 65G tank with 18G sump), the main tank's water level rises very high. I have a full tank height overflow in the corner which rises nearly to the top (very loud waterfall effect, any ideas on how to lower that noise?), and the sump loses all it's water... Well actually about 7 inches or so. Making the water line too low for things like my protein skimmer.

Any suggestions? I can't fill the tank(s) up, cause when I stop the main pump, the overflow completely empties and the sump has about 1cm or 0.5" to spare from the top! Now I know you're not generally supposed to stop the main pump, but in an emergency, power failure, etc....

Oh yeah, one last thing, how much volume do you alot for things like sand and live rock? rule of thumb ratio?

[afss]

I would suggest possibly increasing the flow rate past your overflow. Maybe widening the slots out or something to alow water to flow back to the sump more quickly.

Scott

[afss]

Either that or some how slowing down your pump.

Scott

[Dman]

A ball valve on the pressure side of the return pump to control the flow should help things out.
Give me a call sometime this week, I will walk over and have a look.
Dman
:spin:

[jastonataquapro]

Ball valve helped, I also put in a back flow valve and split the pipe into two outputs both aimed at the front. This has helped keep the sump level up, and lower the noise in the overflow.

However!, now a bubbling noise is happening in the sump. The overflow is sucking in air as it empties, large bubbles escape from te pipe in the sump, bubbling to the surface, making a large noise (kinda like... you know when you're in the bathtub and... umm... you know). Any ideas?

Oh, and I put in one bag of Southdown, I had rinsed it, but apparently not enough. It's been 48 hours, and it's still extremely cloudy the water. I can't see the back of the tank. The filter is *slowly* grabbing all the fine dust, but I'm not sure. Am I going to have to empty this tank just to remove the dust that I didn't remove correctly before I dumped in the sand?

[afss]

For your first problem.... There are different types of stand pipes for your over flow that you can make, perhaps someone with more experience with them could help.
If the buble noise is from the air escaping under the water level in the sump. Raise the drain so its out of the water and have it run down the glass of the tank or something similar. This still won't be perfectly quiet.

Second as the southdown becomes seeded with bacteria etc is will clear out. If you don't have much live rock etc in the tank to begin with the process will take longer. IMO if you add more SD at a later date i would not rinse it as the smaller particles are beneficial. Maybe if you are going to add more at a later date you could seed it in a bucket out side the tank by simply putting some SW in the bucket of sand along with a scoop or two from your existing sand.

Scott

[jastonataquapro]

So what's a stand pipe?

[Dman]

Any chance you can take a digital picture of your tank?
Dman
:spin: