Which sump to use with new tank- refugium or bio balls?

[DI68]

Hi I bought an AquaReef 400 ( already have an AquaReef 300) and the LFS told me to buy a different sump with refugium for an extra $280. I am trying to sell the original sump with bio balls with no luck and am wondering if there really is much benefit in the sump he sold me. I have been reading up on sump vs refugium and people have varying opinions, saying there's risk of the algae taking over the DT and it's just another thing to clean. I have read about reverse photosynthesis to stabilise PH over night and also the refugium reduces nitrates / phosphates and increases oxygen BUT it's meant to be low flow. If it's a compartment within the sump, wouldn't it be the same flow rate as the return pump which is generally high? I have mandarins but am very fortunate as they eat pellets and frozen food so copepods are not a priority but would definitely be a treat to add to their diet. I have attached pics of the tank 400litres) the sump with bio balls and the other one which I am thinking of taking back for a refund. Which is better and what do I put in the refugium? Deep sand bed, LR and chaeto? Thanks.

 

[Lshann14]

I personally use a refugium.

 

[Dav3]

Ditch the bioballs. I would not put sand in the sump/refugium. Just use live rock and a macro algae such as chaeto. It will help with nitrates and phosphates (not to be used as main source of nutrient export however) and won't take over your display. Flow does not need to be low. The reverse light schedule can help with ph swings. Get the largest sump you can fit under your display or even next to it if you don't mind seeing it.

 

[jeffaquarius]

If you decide to cultivate pods in a fuge you definitely don't want them to be washed out by strong current. However, one of the reasons why you need a bigger volume in a sump/fuge is because the wider the vertical area the less water current it will have.