Whether you are keeping freshwater fish or saltwater fish, mistakes will be made! You will loose livestock, plants or corals at some point in your fish keeping adventure. Here’s my Top 5 mistakes that are easily made in both fresh & salty tanks.

5. Not Doing Water Changes

water change meme
Be a hero to your fish, keep up with your water changes!

Water changes are not the most fun thing to do in the hobby, be it fresh or salt, it is an integral part of the hobby.

Doing your water changes will help lower the nitrates (see info about water cycle here), and lower all sorts of other parameters that are bad for your fish. Not only does it lower the bad bits, but it replenishes the good!

Even when you dose various things to keep your essentials in check (being able to chemically sort issues is the only reason this doesn’t make it further up the list), I always imagine it to be like swimming in a public pool, verses running your own bath. In the public pool everything has been treated, so you’re unlikely to get something really nasty but you know damn well some little kid has just peed in there! That’s how I think the fish must feel, they know its ok (they would be dead if it wasn’t), but it must be a relief to get that bit of fresh water! Be a hero, do a water change & keep up with it!

4. Keeping Your Aquarium Lights On For Too Long

Algae issues
No one wants their tank to look like this!

We all enjoy watching our fish, we wouldn’t have them if we didn’t! But, you can’t see your fish in the dark, and when the lights go out most of them take themselves to bed… Surely a couple more hours of light wont hurt?

Wrong! Too much light in your aquarium or lights that are on for too long will eventually cause algae issues (the same can be said for tanks left in direct sunlight). Most algae requires very little light and nutrients to thrive, if you allow it to grow by leaving your lights on, you will soon have a battle on your hands, trying to take back control of your tank.

Stick to 8 – 10 hours a day maximum and keep your aquarium out of direct sunlight. If your tank is in a reasonably dark part of the room, there is no reason why you can’t set your lights around the times you are most often home.

3. Buying Cheap Equipment

Broken Air Line Pump
I am not this technically minded to be able to carry out my own repairs!

You can build a beautiful aquarium on a budget, I’m not saying you can’t. What I am saying is that if you have to buy on a budget (as many of us do), you would be better to either save up for a good bit of kit or buy a well-known, trustworthy brand second hand.

Why? Shelf-life. It’s as simple as that. Everything breaks eventually, cheap equipment will more than likely break on you a lot faster than a good second hand bit of kit, which will mean you have to go out and make an emergency buy to replace the equipment, often having to spend more than what you would have if you have bought the good quality second hand item. Buy something decent first off and save yourself the hassle and future spending!

It is also worth mentioning here that your equipment will last longer if you regularly clean and maintain it.

2. Impulse Stocking Purchases

Coral Eating Fish
Beautiful, but not reef safe!

You go to the local fish store and you see a beautiful fish, it’s the perfect fish to finish your aquarium’s look off and you just HAVE to have it!

No, you don’t! Walk away from the display tank!

Trust me, you don’t want to buy that fish without knowing what it’s care requirements are and if it is compatible with your existing aquarium inhabitants. I realise not all fish take on the traits of their breeds, but it’s not worth the risk. You could end up killing the fish you have just bought, or worse, killing off an entire tank full of fish, plants or corals!

The lesson here, do your homework & research your fish

1. Over Feeding

Overfed Fish
It’s tempting, but just don’t do it!

Be it fresh or salty, over feeding your fish is the beginning of all sorts of nasty things.

Bacteria, ammonia, nitrites, nitrates, detritus, algae, dino’s, cyano… all sorts of things that can fluctuate and cause problems, often brought on by over feeding.

I know it’s hard, my inhabitants seem to be begging for food every time I move towards my tank, and it’s nice to see them happy with full bellies, but you must resist! For the sake of your tank, resist over feeding.

Automatic feeders are a good way to regulate the amount of food you put into your tank, and skipping a day of feeding here and there will not hurt!


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