Is liquid fertiliser fine for fish?

BigJfish12

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Hello all,
Just wondering if it is OK to add liquid fertiliser to a tank with fish? And if it is necessary to fertilise plants or will they be ok without fertilising
 
Liquid aquarium plant fertilisers are safe for fish as long as you don't overdose.

There is a liquid carbon fertiliser for aquarium plants that is made from Glutaraldehdye and that stuff is poisonous to everything and should not be used.

Terrestrial plant fertilisers should not be used in aquariums containing livestock (fish, shrimp, snails, etc) because they have high amounts of ammonia/ nitrogen and this will poison the inhabitants.
 
Agree completely with Colin in post #2.

To answer your second part, is it necessary to fertilize...it depends. Each species of plant needs light of a minimum intensity to photosynthesize, and at the same time it needs some 17 nutrients. Different plants have different needs for light and nutrients; slow growers require less of both, while fast growers require more of both. Very general. Fish being fed produce organics which settle into the substrate and are broken down. Fish also produce ammonia during respiration. Water changes replace some mineral nutrients. Depending upon the plant species and number, these natural nutrients may be all that they need. Or thy may need supplementing either with substrate tabs for some plants, or liquid fertilizer.

Over-dosing not only risks fish, it contributes to problem algae. Ironically, so does not having sufficient nutrients, especially if the tank light is relatively strong. Too much light, either the intensity or the duration or both, can cause problem algae. But so can too little light, if it is not sufficient for the plants. The fertilizer should be a comprehensive supplement. Some nutrients in excess will cause plants to "shut down" assimilation of certain other nutrients. All of this is a real balancing act. And it is always best to use less rather than more, and adjust things according to how the plant growth responds.
 
Ok thanks my plants are/are going to be variegated rush, ambulia and Java moss. Not too sure if I will get any others will see how these go.
 
I use Aqueon plant food and it's completely safe for my fish, shrimp and snails. Java moss need liquid fertilizer IME, and my anubias started growing much better when I added liquid ferts to the tank.
 
Ok thanks my plants are/are going to be variegated rush, ambulia and Java moss. Not too sure if I will get any others will see how these go.
Variegated rush and any rush or reed will die underwater. They are marsh plants that have their roots in water but the leaves must remain dry.

Ambulia loves light and nutrients.
Java Moss will use light and nutrients but doesn't need a lot of either.

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Depending on light, the following might give you some ideas.

LIST OF PLANTS TO TRY
Some good plants to try include Ambulia, Hygrophila polysperma, H. ruba/ rubra, Elodia (during summer, but don't buy it in winter because it falls apart), Hydrilla, common Amazon sword plant, narrow or twisted/ spiral Vallis, Water Sprite (Ceratopteris thalictroides/ cornuta).

The Water Sprite normally floats on the surface but can also be planted in the substrate. The other plants should be planted in the gravel.

Ambulia, H. polysperma, Elodia/ Hydrilla and Vallis are tall plants that do well along the back. Rotala macranda is a medium/ tallish red plant that usually does well.

H. ruba/ rubra is a medium height plant that looks good on the sides of the tank.

Cryptocorynes are small/ medium plants that are taller than pygmy chain swords but shorter than H. rubra. They also come in a range of colours, mostly different shades of green, brown or purplish red. Crypts are not the easiest plant to grow but can do well if they are healthy to begin with and are not disturbed after planting in the tank.

Most Amazon sword plants can get pretty big and are usually kept in the middle of the tank as a show piece. There is an Ozelot sword plant that has brown spots on green leaves, and a red ruffle sword plant (name may vary depending on where you live) with deep red leaves.

There is a pygmy chain sword plant that is small and does well in the front of the tank.

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TRUE AQUATIC VS MARSH/ TERRESTRIAL PLANTS
Lots of plants are sold as aquarium plants and most are marsh plants that do really well when their roots are in water and the rest of the plant is above water. Some marsh plants will do well underwater too.

Hair grass is not a true aquatic plant, neither is Anubias.

Some common marsh plants include Amazon sword plants, Cryptocorynes, Hygrophila sp, Rotala sp, Ludwigia sp, Bacopa sp. These plant do reasonably well underwater.

True aquatic plants include Ambulia, Cabomba, Hornwort, Elodia, Hydrilla and Vallis.

The main difference between marsh plants and true aquatic plants is the stem. True aquatics have a soft flexible stem with air bubbles in it. These bubbles help the plant float and remain buoyant in the water column.

Marsh plants have a rigid stem and these plants can remain standing upright when removed from water. Whereas true aquatic plants will fall over/ collapse when removed from water.
 
Java Moss and Water Sprite are great plants for fry. The Java Moss spreads out in a big clump and bottom dwelling fry and fish eggs can remain hidden.

Water Sprite normally grows on the surface and has lots of roots and branches and is an ideal plant for surface dwelling fry to hide in.

Java Moss can also hide snails, hydra and planaria so keep an eye out for these things.
 

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