Who Gives A Fish Forums

I'm having some issues keeping my 240litre tank clean, it's an malawi mbuna set up with loads of rock, so the actual water volume is way less than 240 litres. I'm running a fluval 305 which is supposedly suitable for 300 litre tanks. I've got 35 juvenile mixed mbuna - yellow labs, acei, white top afra hara and zebra afra hara. I'm thinking of adding the juwel jumbo internal filter back in and swapping out the air wall for some sponge filters. Would this make a significant difference or am I just overstocked? I've got other tanks available but I'm unsure how many fish to keep in the main tank. I'm really looking for advice on filtration vs stock levels, I don't mind cleaning the tanks but I dislike disturbing the fish too much.

I'm in a similar setup and I've got to say, no issues at all.

When you talk about trouble keeping your tank clean, what exactly do you mean by clean? Remember, your filter is mainly for biological filtration, with a bit of mechanical thrown in.

If it's the growth on the rocks that's the problem, adding more filtration won't make a huge difference. Lighting's a big factor - too much and they go green, too little and they go brown. And let's not forget, bad water can turn them black.

Overfeeding, overstocking, and not doing enough water changes all add to the problem.

The 305 was designed for a 240-litre tank, so it should be able to handle it.

Just the front glass gets green after a few days, by day 3 the back's gone green too and by day 5 it's like I've not cleaned it in ages. Added the juwel jumbo internal filter but made no difference. Took it out, don't think it looked right anyway. Lights are two 54watt t5s, on from 9am to 6-7pm, so yeah, that's too long. Fluval 305's running 2 ceramic bags, 2 carbon bags and 2 carbon sponges on top. Ordered the two sponge filters, hoping they'll make a difference when they arrive. Feeding spirulina in the morning and 2 frozen malawi mix in the evening, trying to keep it balanced.

mate, your tank layout looks sweet, got me feeling like mine's not up to par lol

I'd suggest limiting your lighting to 6-7 hours a day max, that might help with the green glass issue. In terms of your Fluval 305, I'd recommend swapping out the carbon bags for more ceramic and a coarse sponge - that'll give you better filtration.

You could also consider replacing the carbon pads with a coarse sponge and a fine sponge. To be honest, carbon's only really necessary if you've got tannins or meds to remove, so ditching it for extra sponges will increase your filter's capacity and quality. Just make sure to do it gradually, so your bacteria can colonise the new media without causing a mini-cycle.

Sorted loads of bits to start swapping out, the sponge filters turned up today so they'll go in later. Was getting a bit fed up with the air wall anyway, seems it's down to the lights and filter set up. Was thinking I must be doing something wrong, I mean the tank's probably only got 180 litres in it. Cheers for the advice mate.

Cheers mate, spot on advice. Swapping out the sponge has made a big difference, still got a few more to change but it's been 2 days and the front glass is still clear. Fingers crossed it keeps up.