AquaticEco.com sells them here cheap and the shipping might be a bit, but given the added cost locally, it might not be that bad, buy a few and they do last a while BTW and are large.

Regards,
Tom Barr

Hi Tom, thanks for all your help with this, it's appreciated.

With regard to the filter 'socks', which do you prefer? I see you can get nylon or felt, felt being about $10 and nylon about $45. Is there an advantage to the more expensive items? Do AquaticEco.com export to the UK BTW?

Yes, they send to UK

Regards,
Tom Barr

Hi one and all, I'm back!

I've now put in the substrate and I'm waiting for some filter bags to be delivered (I managed to find a UK distributor: TMC Ltd if any UK readers are interested)

It now leaves the lights to consider.

It's a 6' 3" tank, with a depth of 19" to the substrate, about 113 UK / 135 US gallons.

I have a 150W 6500K metal halide pendant going spare now that I've reduced the lighting over my Juwel Trigon tank. I was thinking of getting another of these and having a pair of them over the tank or do you think that would be too much? (about 2 - 2½ WPG; do you calculate it in UK or US gallons?) Or I can get a 70W and convert my existing 150W to 70W as well.

With a tank that long you'd need 3x 150w.
I used that on a 135 gal 6' ft tank.

You can raise and lower them as needed.

Up to you really, note, a pair of 39w x 2(4x39 w 36" T5 bulbs) would also work.

I prefer even light coverage light for the tank

Ideally having 4 x 70 w would be nicer.
Just 1 MH every 2ft is a min

Regards,
Tom Barr

Thanks Tom,

When I first took up this hobby I thought lighting was rather a simple subject. It wasn't until I started reading through your site that I started to learn more. Maybe I should have paid more attention all those years ago in school

When I had the 150W over my corner tank it drove really high growth rate from the plants, as well as some algae. This is why I've now reduced it to a pair of 24w T5s.

Did you find that 3 x 150W over your 135G gave very fast growth? I found that the demands on me of a fast growth tank was too high. What little time I had off work was spent up to my armpits in fish tank! I think I might go with a bank of 70W. You said one every two foot?

The tank is now taking shape. Once I get the filter bags and alter the sump as per your recommendations I should have the CO2 stable. Just the lighting and then it'll be time to plant!

With MH's you can raise them up or down to throttle the amount of light needed.

I use them for open tops.
Folks that complain about the light/want enclosed hoods should consider building them into the wall and putting a door over the tank for access rather than traditional hoods.

This allows much better access.
Use a car rear door shock arm gas strut for this. That allows easy opening and closing.

You can build a large high hood(say 24" tall) for this if you want, but make sure the lid is front facing, and there is no lip on the front that you have to hop over to work inside the tank.

Those are terrible designs and should never be suggested or added/bought etc.
Always make access easiest.
Same with water changes.

Regards,
Tom Barr

That sounds like a good idea.

For me though, I like open tops. I removed the covers from my Juwel Trigon and have no cover on my new 6'.

Since changing my corner tank from the 150W 6500K MH to a pair of 24W T5 7800K I had a bit of a BGA attack. I've done a cover up and water changes which has knocked it back. I read somewhere that plants can take a temporary hit if there is a big change in lighting. Is that what I'm seeing here?

Perhaps but generally they do fine with good nutrients/CO2.

BGA and most algae are more related to poor CO2 than anything else.
Folks change lighting, that obviously changes the CO2 uptake with the plants as well.

Most adjust and tweak the CO2 a bit before settling in with a light system.

Regards,
Tom Barr

I don't think I can push any more CO2 into the tank!

I built one of your internal reactors and it works well, putting out a nice fine mist.
In the UK, we have access to a commercial CO2 test that works the same as your CO2 drop test indicators and it shows a nice light green / yellow indicating a high CO2 content. I also have a pH monitor which shows a pH of 6.1-6.5, depending on time of day, with a kH of around 130 mg/L (a Tetra kH drop test)
If I try and push a little more in and the pH drops to 6.0 or less then the fish start looking very stressed and head gasping for the surface

I can't think how I can improve it any. Nutrients you have noted before and seem fine.