In message , Elaine T
writes
sophie wrote:
I have a four foot coldwater tank, which until a month or so ago had
no hood and no lights - it gets slanting sun in the afternoon, and
the only plant I had in there was creeping jenny, which I appreciate
isn't an aquatic plant, but has grown happily for me over about eight

A month or so ago I added dojo loaches, who are notorious jumpers,
to the tank, so I also added a hood & a light, and some anacharis -
which did quite well in an unlit tank for me last year until it got
eaten...
The lighting is pretty inadequate for plants at the moment - I think
it's 38 watts (fluorescent) and the tank is about 46/47 US gallons,
and I've started to get a fuzz of green algae on the
stones/shells/wood and plants - and on the tank glass. I'm not fussed
about it on the furniture, but I don't like it on the glass or plants much.
I have an idea that I need to: put another bulb in and add more
plants. Would this be a good plan? Part of me thinks I would get more
algae, part of me thinks that with more light the plants would be
able to out-compete it. I also think that maybe frequent water
changes for a few weeks might help? Nitrates are somewhere between
12.5 & 25, I think closer to 12.5 but the kit (Tetra) only has those
two options.

You are definately short of light for plants, and yes, adding more
light and plants can shift the balance away from algae. It does take a
bit of care to get the tank really going well, and you can still get
algae blooms even in heavily planted tanks. To find a balance, the
plants must be fertilized properly with a trace element mix, iron,
potash, CO2, and sometimes even nitrates and phosphorus. You also need
lots of plants, so that they use up everything before the algae does.

In the short term, water changes will help with the algae if your
tapwater is lower in nitrate and phosphates than your tank.

You're confirming what I thought, thank you! I think I shall be getting
myself a copy of "The Ecology of the Planted Aquarium" and going about
this in the lowest tech. way possible, and the most educated way
possible. In the meantime I'm wondering about shovelling more of the
creeping jenny in for the short term till I work out what I'm doing, as
it seems pretty happy in there and it's free.

If this is a good idea, are there any other coldwater plants suitable
for a beginner? I'm coping with a small (overstocked) tropical tank
fine, but I'm finding coldwater plant advice hard to get in the two
(very nice) LFS I go to

I'm starting a pond outside and just did a bit of research on coldwater
plants. I ordered Cambomba carolinia, Vallisneria americana
(needs 67 degree water), and Egeria najas (a prettier form of
anacharis) to go out in the colder water. Myriophyllum aquaticum
(parrot's feather) and many of the native Sagittaria species also
prefer cooler water. For more ideas, try going to a pond store instead
of a tropical fish store.

I shall be checking these out, thank you!

All advice very gratefully received...

One other thing - I don't know of any coldwater algae eating fish, but
some of the Japanese algae eating shrimp are temperate and handle cold
water perfectly well. There's one called the Amano shimp and another
called Tiger shrimp. If you get a bunch, they'll eat the algae off of
the plants and furniture. You may be stuck scraping to clean the
glass. Algae magnets work great and you don't have to dunk your arm
into that cold water. Brrr...

shrimp sound entertaining. Are they:

a) small enough to get eaten by the goldfish
b) big enough to eat minnows?

I've got chinese algae eater - and yes, I do now know their
reputation :-( But for now - I think perhaps it's the low temps he's
been acclimatised to - he is still very small and non-aggressive. I
think it's a space thing; he was very very jumpy & territorial in the
small tank, but in here he's fine. Spends all day eating, but sadly
there's just too much algae for one CAE, and now I know more about them
I shan't be getting another, I think it would be a Very Bad Idea. Shrimp
sound very cool if they would fit in, and I can cope with the front
glass - I grew up on the coast in East Anglia, so cold water-induced
numbness is pretty familiar to me.

Many thanks for your help, Elaine; I'll be looking at those plants.


--
sophie