Recently while perusing one of the many Facebook (FB) groups I belong to, I encountered this question:
Is having a sump tank more expensive and more hassle than a regular filter?
I pondered that question for a few minutes. It is an interesting question because, while sumps offer numerous filtration advantages, they also can present some challenges beyond those encountered with typical power filters (e.g., external canisters, HOBs).
The question of expense has a bit more straightforward answer – typically “yes.” This is assuming the OP (original poster) on FB was referring to up front or initial costs rather than maintenance costs. It also assumes he/she meant a canister or HOB when they say, “regular filter.” Sumps (or wet-dry filters) are typically reserved for larger tanks, which IMO are tanks 75g or larger. As such, the cost of setting one up is generally higher than other filtration for the same size tank because of the components needed. For example, a 100g aquarium can easily be filtered with a single large canister or maybe even a couple of HOBs. Going with the latter, the “up front” cost would be ~$100 (USD). However, a typical sump (or canister) for a 100g aquarium might be twice that (assuming you invest in a quality water pump and a commercial, off the shelf (COTS) sump filter box).
For a 100g tank, I would probably target a pump capable of at least 750 gph at 6′ head pressure. There are many submersible pump manufacturers, and a good 750 gph pump will cost $150 (USD) or more. A good, basic off-the-shelf sump will cost ~$300 (USD). I can recommend some good quality submersible pumps, even quiet ones, so reach out to me if you’re interested. Add in hoses, connectors, media, and other supplies, the total cost for a solid sump set-up will be ~$550 (USD). Of course, you could build your own and save money on the sump tank. A quality pump will still be needed, though.
However, there are lots of variables to consider when deciding upon the type of sump and the pump for it, which will affect expenses associated with initial install and maintenance. What is the tank stocked with? How important is filter noise? Is the tank planted?
I think in the case of OP’s two-part question, the answer is heavily dependent on the size of the tank and what’s in it. If you have a behemoth tank (>300g), appropriately filtering with anything other than a sump will not be cheap. For example, a single Fluval FX6 retails for ~$350 (USD), on average. I wouldn’t filter a tank that size with a single FX6. In fact, I am confident most aquarists wouldn’t run a single FX6 on a 300g tank.
Running two FX6 canisters on a 300g would thus cost well over $700 (USD). You could set up a sump on that size tank for a similar cost and have much better filtration than two canisters.
On the other hand, for smaller tanks (<75g), there really is no point in a sump. Lots of people use HOBs on smaller tanks, and for good reason. They’re less expensive, easier to maintain, and just get the job done.
Referring back to the OP’s question, expense and hassle are two separate issues. IMO, sumps aren’t anymore hassle to maintain than other filtration types. Setting them up appropriately requires a bit more plumbing/filtration knowledge than a typical power filter but once in place, cleaning and servicing the sump doesn’t present any greater challenges than the other filtration types.
I recently posted about filter choices, if you’re interested in reading that too.