Tank help for my husband please!

[ApplebyMennym]

DH is in charge of the fish tank at his work. It was a baptism of fire since he didn't have a clue when be first started, he just took an interest. In the months following he's gained a lot of knowledge about it and it's pretty much his new passion! He's now been told he can buy some stuff to tart it up, and he's looking for some help from the experts. I know NOTHING so the following is in his words:

The tank is currently home to one large pleco and several swordtails, male and female. At regular intervals, the glass becomes covered with algae and there is a large population of snails that are unwanted. Can anyone advise on which species of fish would help keep the algae levels and snail population down?

He's looking to buy an air pump, two filters, a bubble wall and some new gravel, any recommendations on these would also be much appreciated.

Thank you!

The algae is probably caused by excess nutrients and the snails will be caused by overfeeding- adding fish won't solve either of these problems and could cause more.

I would advise getting a water test kit so he can see what the cause of the excess algae is. A little bit of algae is perfectly normal and you can get glass scrubbers to clean it off.

To help cut down the snail population, only feed what the fish can eat in 2-3 minutes and then scoop out what's left over (and hide the food from the rest of the office!). If there's no food then the snails won't breed as much. You could get some assassin snails but you'd still need to watch the feeding because they will scavenge for leftover food too.

Do you know how big the tank is? Most species of pleco get very large (some about 2ft) although there are a couple that stay small-ish. If your DH can get a photo then I might be able to ID it.

Male and female swordtails, yikes. They are livebearers and breed like crazy. If he could rehome the females then that will stop him being overrun with babies. How many are in there?

You say he wants to buy a filter... does that mean there isn't one in there yet? They come in various sizes so if you tell us the size then people can recommend the best type and size that you need. Air pump size isn't as crucial but generally larger pumps aren't so good for small tanks. Larger pumps= more bubbles and a more powerful stream so if there are little fish then stick to a smaller pump.

If he's looking to redo the whole tank with new gravel then that's a bigger job but I can do a step-by-step guide if you want.

Sorry for the essay, hope it's helpful though.

That is exceptionally helpful EauRouge thank you SO much. I will ask him your questions later. I think there already is a filter but not a very good one, I seem to remember him saying.
I think he does want to re do the whole tank.

Message from husband:I'm glad I won't need more fish, keeping the swordtail population down is quite a job but luckily our handy man has a tank in his workshop so he helps keep numbers down. I estimate the tank to be somewhere in the region of 100 litres. How can I keep nutrient levels down? I'll get a water test kit when I shop for the rest of the stuff I'm getting for the tank.

I have an algae magnet but sometimes it doesn't shift the algae and I end up using a glass scraper.

Limiting feeding could be a problem as I'm not there all the time and have to rely on other staff to help with feeding but if I tell them all to monitor it we might be able to keep the snails under control.

As for the filter situation, the filters are two different sizes. One is the largest internal size they do as far as I know and the other is the smaller type. They seem to be struggling to manage filtration of the tank and this could be because they are very old and worn out (one if them has magnet damage and needs to be tapped on the propeller to make it spin) or it could be the filter elements which are both at least five years old. I was considering an external filter but may buy two tetra IN 1000 plus filters. I've looked at several components for the air pump and it is as much for aesthetic effect as anything.

Thank you so much for taking the time to help me. I don't really have anyone at work who I can ask for advice.

The nutrients that can cause excess algae are nitrAte (NO3), not to be confused with nitrIte (NO2), and phosphate. NitrAte is reduced by doing regular water changes. Around 30% once a week is a rough guide but it might be more water than that or more often depending on stocking levels. NitrIte should always be zero in a healthy tank. Phosphate is in tap water and it can be higher in some areas than others. You can get phosphate removing stuff to put in the filter if it's a problem.

If you're not there all the time and you're worried about colleagues overfeeding then you could maybe get an autofeeder. I've got this one and it's very good.

An external filter might be best since it's a medium-sized tank. You need to clean the media (sponges, bioballs etc) in water taken from the tank- the chlorine in tap water will kill the good bacteria and cause all sorts of problems. You can probably do this once a fortnight but experiment and see how long it takes to get clogged up. It doesn't have to be really clean, just clear enough to let the water flow through properly.

Filter bacteria need three things; water, oxygen- they get this from flowing water- and food, which is ammonia produced by the fish and then nitrIte produced by ammonia-eating bacteria. If they are denied any of those then they start to die off, so don't let the filter media dry out, or switch off the filter (unless cleaning it), and if the tank is emptied of livestock for any reason you'll need to add a bit of ammonia to keep the bacteria going.

100 litres is medium-sized but may not be big enough for your plec longterm. Has he got any distinguishing features at all, like a bristly face?

Hope that helps and that I didn't witter on about bacteria too much

He says you're an absolute wonder.

He's on holiday from work this week but will ask someone to take a photo of Sharky (the Pleco) for possible identification purposes.

He's looking at the AquaManta EFX200 external filter, (he was chuffed when you said an external filter would be best as that's what he wanted) do you know anything about this one?

He doesn't think the work fund will stretch to a new tank, so if Sharky is going to get too big for the current one he will probably have to be rehomed (he wants to bring him home but we haven't got room for a tank big enough!)

Thank you for all your help, I'm sure we will be back!

Never used that particular filter, but it looks OK. One thing to note is that it comes with carbon and phosphate filtration- I wouldn't bother with this unless you have high phosphates or you need to remove something from the water (any sort of pollutant or medication for example). Carbon needs replacing every 4 weeks and can end up costing a lot. It's good to have some on stand-by just in case but there's no need to use it routinely if the livestock level isn't high.

There are fish rehoming groups on Facebook if Sharky needs a new home, or sometimes aquatic stores can house them in display tanks.

Sorry, that might have been a bit vague. The filter looks good. The carbon and phosphate filtration are separate sponges that you can just leave out when setting the filter up. Most filters come with these extras now and manufacturers recommend it because it makes them lots of ££££

A good way to control the algae and snail levels would be to get a few assassin snails (they'll eat the 'pest' snails and look much cooler) and some Amano shrimp (they'll eat the algae and are incredibly entertaining to watch). He should definitely get a filter too, that should help with the algae problem too. I'm jealous of your husband, I want a fish tank at work too!