Neutro Bromo Blue 100ml

 Sold Out 
Want Delivery on Wednesday 27 October? Order in the next

and choose Express Delivery at checkout.

Better together


Neutro Bromo Blue solution can be used with all drop checkers and is the only solution you should be using in a drop checker. Does not require mixing or anything else.

Directions: Add a few mls to your drop checker, then pop the unit directly into your aquarium and wait to see the colour change. Ideal colour to aim for green. Blue means too little, yellow means too much. Adjust your CO2 output accordingly.

You may also want to consider the 3ml Pipette which is used to dispense the Bromo Blue liquid into the drop checker.

If your drop checker stays blue you simply need more CO2. Simple as that.

Let us notify you when this product is back in stock!

Simply enter your details below and we will send you an e-mail when “Neutro Bromo Blue 100ml” is back in stock!

We will not send you any other e-mails or add you to our newsletter, you will only be e-mailed about this product!

also purchased

by John K.
ready to use, large bottle and good value

by Diogo F.
Fast delivery and easy to use. Does what he says on the tin.

by Stuart W.
A good price and fast delivery.

by John W.
The only drop checker fluid l use saves any mixing and accurate

by Niels v.
Does the trick! Arrived super quickly. Great advice from Richard - so very helpful

by brian k.
good no problems

Ask a question about this product
hi my Solution has gone green in the bottle is this sill ok to use ?

The solution has to be blue in order to work properly. You need to replace yours.

How often do I need to change Neutro Bromo Blue solution in Neutro Drop Checker and how much solution are you supposed to use ?


Most change it every few weeks and use enough bromo blue to fill your drop checker at least half full.

What is the shelf life of this product once it is opened.

Depends how it's stored and how often it's opened etc. But about 2 years in ideal conditions.

I have just set up my planted tank but I have not started introducing CO2 yet. It has been running several hours now however I can already see the color has turned green. Does this mean there is enough CO2 in the water for the time being or is it an indication of something else? Many thanks...

If you have not introduced any CO2 there can't be any in there. The colour change refers to your pH which is what a drop checker actually measures.

how is this best stored ? mine has gone green in the bottle after just a couple of months

Pls contact the office with your order number and we will issue a replacement :)

I'm not familiar with drop checkers - is Bromo Blue safe for fish? I often find that rubber suckers come away from the aquarium glass after a while and it looks as if the Bromo Blue would mix with my aquarium water if that were to happen.

You only have about 2ml in a drop checker so it won't do much harm. If in doubt always do a water change. I also recommend replacing your suction cup.

My solution remains blue no matter how much CO2 keep pumping from the canister into my tiny 25L fish tank. Not sure what to think, I changed the solution again but still blue. Please help.

You need more co2 or better water circulation

Hiya, my solution turned a 'dark green' do you think i should increase the bps to make it lighter as seen in the pictures?


Yes - dark green is not ideal. Light green is much better.

All changes to CO2 must be done slowly over several hours (preferably days if you have livestock)

Ask your question here