Question re: Changing from internal filter to HOB

Hi. Bit of a noob, so excuse the question.

I have a Resun CS400 internal filter that came with a 2ft used tank I bought but it exhibits problems in that it isn't aerating properly (separate airline) and doesn't always switch on again after I switch it off. Because of that and the fact it takes up space in the tank and suction things aren't working so well anymore, I changed it to a Dophin SH280 HOB.

Now my question is - the Resun CS400 is missing its' charcoal element but still has two or three sponges inside that are heavily laden with bacteria and what I think are ostracods - great. But the Dophin only comes with three little card-type filters which have a little bit of charcoal in them and that is it.

Filter media looks like this : http://www.sagaraquariumonline.com/wp-content/uploads/2017/03/71LridHcd7L._SL1200_-2.jpg

At the moment I am running both filters in the tank - but I am concerned that the new filter doesn't really have a "place" for the bacteria to establish itself without a thick sponge being inside it? The only sponge that is part of the SH280 is on the intake pipe.

Your thoughts? I saw in another thread it was suggested that the existing sponge filters from the old filter be cut up and inserted into the new filter?

 

Pop a sponge filter sponge over the intake(mechanical filtration) and take all the inserts out and put matrix or ceramics (Biological filtration) in the back. Maintenance is easy as you just pull off the sponge and rinse it in tank water. The sponges that comes with these over the intake are a bit porous and allows particles through, sponge filter sponges catches more but needs to be cleaned more often though. I'm running them like this and it works very well.

 

In the slim Dophin SH280 there doesn't seem to be any space to add additional filter media.
Perhaps you could cut a piece of the old sponge to the size of the combined cartridges, and use that to seed the filter.

Personally I prefer the Cascade HOB range, as they have enough space to add filter media.
I have removed all the cartridges, and replaced them with Seachem Matrix in a small mesh bag.
To me, it provides a better breeding ground for beneficial bacteria than the cartridges that you keep replacing.

 

Hi and welcome to the forum

I agree with the advice given.
Would definitely take the cartridges out and replace with some matrix.

 

If you take out those crappy inserts it frees up some space, not much tho.

 

Thanks. There is *some* space, albeit a small amount. Also the filter cartridges seem to be able to be slotted forward or back a little bit. Is it not worthwhile keeping the cartridges in place but putting the Seachem Matrix behind or in front of them?

See here:

 

I wouldn't bother with the supplied cartridges, as they are basically activated charcoal with a thin screen to keep dirt out.
If it was me, I would dump all the cartridges, and fill the filter with as much Seachem Matrix as I could.

 

Cool - just thought the screen might have been worthwhile but if nothing but Matrix is better, I'll just go that route. Thanks all!

 

Don't forget the intake sponge, you don't want any dirt to settle on your matrix as that you want to leave alone and not fiddle with it too much.

I use these.


What you do is, the intakes of these sponge filters is a tube with holes in them. You cut it off and use that whole thing as the hob intake. I attached mine to the hob with a small piece of extra tubing that fits over this and the hob piping. It is quite a formidable little filter now after this mod, and you have a spare.

Here's what it looks like when done.

 

Thanks, will give this a go!

 

Not sure how your slim compares in size vs mine ..



https://www.tropicalaquarium.co.za/threads/pimp-your-hob.6952/page-3

I like small round media for pimping.

Later Ferdie

 

R1 coin to show the size of the media and the space in the HOB.

Later Ferdie