Stupid Newbie Questions

[satellite4881]

Ok. I have moved and have my 75 gallon tank all built and painted. I have the plumbing set up with a custom sump. I need water, rocks, sand and then im ready to go. my questions are this

How big of a return is needed for this system? it goes up about 4ft.

How much live rock? 50?75?100lbs?

Is a 1.5/2" sand bed ok?? I have a mix of southdown and LS I was going to use.

I have 2 koralia 3s and 1 koralia 1. Is that enough flow? Where should I position them??

Also if I use completely cured LR in water will it be a full cycle??

TIA

 

[drummereef]

The recommended sump turnover is 3-5x the system display. So, for your 75g that would be between 225-375gph. Nanogurl actually just went through this decision in her thread. She decided on the Mag 5. I think it's a good choice. You are going to want to make up the rest of the flow in the display with powerheads. A minimum of 20x turnover total is recommended. I would use all the koralias which will give you roughly 30x. As for the live rock, I would do at least 1lb/gallon. 100lbs would be better if you can do it. The cycle is dependant on how much die-off there is. You won't really know until you get the tank set up and start testing for ammonia, nitrite, and nitrate. If you get fully cured rock, the cycle will be shorter but most likely you will see a small cycle. Testing is the only way to know for sure. For the sandbed, if you are going for a shallow sand bed I'd do 1" or less.

 

[satellite4881]

Thanks so much. I have a brand new pump thats 250gph but I figured its too small. I guess I could try it with the 3 powerheads.
As for sand I will stick to an 1" or so then.

If I get one 30 lb bag of LS is that enough to seed the southdown I have??

 

[drummereef]

All you really need is a cup of established sand to seed the sandbed. Your live rock will also help seed it. I'm not a big fan of the live sand in a bag thing. Haven't had good experiences with it.


Just remember head loss when calculating your return pump. You want the value to be 225-375gph (3-5x) after headloss.

 

[Konadog]

Good info so far.

Here's a little more:

Check the Head Loss Calculator with any pump you think you might use to see if it will provide the flow you need.

With the rock, it also depends on what kind of rock you are getting. Some rock is lighter than others so #100 of on rock may only fill 1/2 the tank, while #100 of a different type will fill it. Read this for info

If your sand bed is for looks, any depth that you choose will work, if your looking for the benefits of a deep sand bed, 4 to 6 inches is what you will need. Here's some more reading, How Sand Beds Really Work For figuring out sand bed depths, Check here.

Good luck with your new tank!