I do not think it is tannins.

[piao liang yu]

I have a 60 gallon 48"x13"24" tank. One AC110 and one AC70 with two bubble curtains in the back of the tank. I have one T5HO with one rosette bulb and one white bulb. I have several plants that range from anubias, amazon swords, lots of java moss and some java fern. I dose with seachem flourish comprehensive twice a week and dose with seachem flourish excel daily.

My question is just a few days after I do a 50% pwc (performed weekly) I get what I thought were tannins in the water. My purigen gets dark brown within days. I am starting to wonder if it is organic material causing the problem though. My prefilter sponges on my HOB filters get to where they restrict flow after just a couple of days. I have to turn everything off and clean them thoroughly with a lot of muck and gunk washing out of them. I really could clean them every two days. What is going on there? Why would I have such a problem with gunk like that? The following is my stock.

10 neon tetras
4 otocinclus
3 guppies
3 angelicus botia
3 red wag platies
1 Dwarf Gourami
colony of RCS (plenty of hiding places and moss)

I do have lots of driftwood.

Oh, Ammo 0, Nitrate 15, Nitrite 0, PH 7.6

Would a UV sterilizer help with this?

 

[piao liang yu]

The gunk that i wash out of the pre filter sponges is black if that helps anyone. I initially thought the issue was just a problematic tannin issue from my driftwood because that is the color it becomes after a few days. It was after repeatedly washing these pre filter sponges that i realized once i clean most of the gunk out of them the water rinsing in the sink becomes the same color as the "tannin" color i initially suspected. Anybody have any experience with this and if so did you find a remedy?

 

[Abiduwhabi]

So, you have a lot of driftwood. Did you soak it, boil it, anythign like that?

Just to clearify, your filters become clogged up? When you rinse the filters does stuff come out, or is it just like colored water?

 

[FallenRedeemer]

This sounds very similar to an issue I was having. I would clean the filters and within 2 days I would have to clean them again. I just kept up with my water changes and the problem went away. I have a big piece of driftwood in my tank and live plants as well.

 

[piao liang yu]

So, you have a lot of driftwood. Did you soak it, boil it, anythign like that?

Just to clearify, your filters become clogged up? When you rinse the filters does stuff come out, or is it just like colored water?

the driftwood came from established tanks from LFS. I have had it for about 10 months now. And it is the prefilter sponges I am talking about. I cover the intakes of my filters with fluval edge prefilter sponges. within two days or so flow is restricted. I have to turn it off and pull those pre-filter sponges off and wash them in fresh water. They are slimy and gunked up. Cannot understand how it gets so messy as I only feed once a day and do 50% weekly pwc's. It is not tannins. Tannins are just a discoloration if I have researched correctly. This stuff is slimy and black, very dirty.